Use The Prefect Retrofit Snow Guard Bracket H – Classic or Apex For Snow Retention

One of my older relatives used to say, when confronted with a dilemma, “What to do, what to do….”  It made me chuckle!

But, this phrase describes a dilemma for people confronted with snow and ice avalanching off their already installed roof.  They want to keep the snow up there

snow clips, snow guards, snow bracket

rather than down there

Snow Avalanche Off A RoofFalling Snow in Park City, UT

but what is the best solution?

First of all, retrofit is similar as well as different from new construction.  Basic questions need to be answered for new and retrofit construction.

  • What is the slope?
  • What is the snowload in the area?
  • What type of roofing product is being used?
  • What type of sheathing is under the roofing material?

For retrofit, snow retention installers don’t have the luxury of applying the snow retention devices as the roofing material is installed in a new project.  This is when “What to do, what to do…” might be heard under their breath!

How do you keep snow and ice from falling off while also maintaining a water-tight system when the roofing is already on the roof?  How hard is it to do this?

Contractors need a simple and effective solution.

For asphalt shingles, simulated shake, and other similar roofs, using TRA’s Snow Bracket H – Classic or Apex, there is no need to pull back the headlap to install a device. Butyl or caulking can be applied on the surface of the roofing product, then the bracket is installed directly into the sheathing using screws.  A clip is then placed over the screws.

Snow Bracket H – Apex

Snow-Bracket-H-Short

Snow Bracket H – Classic

Easy. Effective.

The reason this system will work on retrofit is because TRA’s engineering is done using the specific factors as mentioned above.  When installed using the engineered layout, the roof will now hold back the snow and ice that would have fallen off, damaging people or property below.

At TRA Snow and Sun, we help you find an Engineered Solution.  Call us for a free layout, provided within 2 working days.

Snow Bracket H – Classic or Apex

Designed for most roof types

Available with or without fastener cover clip

Can be powder-coated to match roofing material

Available in 16 g steel, 48 oz copper, 26 g Cor-Ten, 16 ga stainless steel, .063″ aluminum

Finishes – Electro-galvanized, hot-dipped galvanized, mill finish aluminum, copper or Cor-Ten

Power-coating available in many colors.

When Does Your Roof Need Snow Retention?

Are you hearing loud noises coming from your roof?

This can be a sign that snow is sliding.  Beware the next time you open the door to go outside especially if your door opens where snow falls.  Deaths have occurred when snow slippage is imminent and someone slams a door.  Just the vibration creates an avalanche.

Are you noticing large pieces of ice and/or snow coming off in big chunks?

Are pieces of your gutter coming off with ice at the eave?  Ice is a heavy and powerful factor in gutters becoming disconnected from the structure.

Are there high spots of snow and ice piled at the eave line on the ground?  This might mean that snow or ice has come off that place during the winter.

If you answered yes to any of these questions, continue reading.

People die due to snow and ice sliding off roofs. This is extremely tragic and often avoidable. Use roof snow retention for these reasons:

  1.  Damage/Injury – People and property can be struck by snow and ice falling from the roof. Property damage and injuries, even deaths can occur when snow is not properly retained on a roof.
  2.  Limited Access – Entrances to buildings can be blocked by snow and ice that falls from a roof.
  3.  Roof Damage – When snow and ice masses slide off a roof, costly damage occurs.

It is especially important to install snow retention above:

  • entryways
  • walkways
  • gathering spots
  • parking lots
  • drive-through areas
  • expensive landscaping
  • ground mounted mechanical
  • roof protrusions such as plumbing vents

Can Your Building Support the Weight of Snow Retention?

You might wonder if your roof can support the weight of snow and ice staying on the roof. If your home is less than 40 years old, the answer is probably yes.

During the 1970-80’s, most states adopted building codes that required structures to support the weight of the building materials (dead load) and the weight of the snow, ice, water, people, etc. (live load). By the year 2000, international building codes were universally adopted with similar standards. So, if the structure was built post 1975, you are unlikely to have any structural problems when keeping snow on the roof (it also helps insulate your roof, saving heating costs!).

 

Could An Urban Roof Avalanche Affect You?

Ice_dam_slate_roof
 

In the next couple of days, a wintry mix could make things dicey on the mountains and even in your neighborhoods. That’s why avalanche forecasters are urging caution. Nicole Vowell reports from KSL Channel 5 New.

 

 

To help avoid such avalanche conditions there are several factors that one must evaluate when determining if a particular building requires a snow retention system.

The first question you should pose is “What would happen if snow slides off the roof?”

The second question is “Do we care?”

When snow slides off of a roofing surface, it can come crashing down or slide off and then piles up on whatever is below the edge of the roof. Snow retention is frequently used to protect landscaping around the perimeter of the building, to protect guttering systems around the edge of the roof, and to keep snow from piling either on a lower roof level or decks, sidewalks and at garage entrances. If nothing below the roof can be damaged by this avalanche of snow and ice, it may be best to let the snow and ice slide off unhindered.

However, what if what is below the roof could be damaged?

WHY SNOW RETENTION IS NEEDED

During the winter months, as snow accumulates on your home, gravity will begin to pull it down the slope of your roof. There are many reasons this can be harmful to your home or even dangerous. In worst structural cases, this can lead to damage to costly gutter systems, structural damage to lower roof levels, and even destruction of mature landscaping around the perimeter of a home.

Low-slope roofs with parapet walls naturally keep snow and ice on the roof. On a sloped roof, however, large chunks of snow and ice can slide off as the snow melts. Avalanching snow is probable on roofing systems with a steep enough slope and/or a low coefficient of friction. This is especially dangerous for pedestrians walking below.

CHOOSING THE RIGHT SNOW RETENTION SYSTEM

There are many types of roofing materials, each has advantages and disadvantages and each should be considered when determining the placement of snow retention on the building.

When considering whether to install a snow retention system on your roof, you may first want to consider what type of roof you have. Will your roof allow snow to slide? Probably.  In places with heavy snows, like areas in Utah, it is common for snow to slide off of all types of roof systems, leading to heavy ice and snow build up in gutters, which causes damage over time. If you have a metal, tile, slate or membrane roof with a pitch of 1/12 or greater, snow will definitely slide off and cause problems.

WE CAN HELP…

TRA snow retention systems are available for all types of roofs and come in a variety of options. The specific snow retention equipment recommended for your roof will depend on the type of roof system installed, the pitch of the roof, snow load, sheathing type, how old the building is and budget.

Our snow fences, brackets, and clamps are all types of snow retention systems that prevent large sheets of snow or ice from falling off a pitched roof. The systems hold the snow on the roof so it can gradually melt off, preventing damage to people and objects below.

At TRA Snow and Sun, we engineer and layout each project free of charge using the unique factors specific to your project. TRA Snow and Sun representatives will work with you to design the most efficient snow retention system. We can design your roof to work with a variety of applications. Just give us your project details & we will design your Snow Retention System to fit your project. For more information, call Ben Anderson at TRA Snow and Sun at 800-606-8980, ben@trasnowadsun.com, or visit: https://trasnowandsun.com/                                                                                                          

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Slogan

Why is Metal Snow Retention Better Than Plastic?

Every once in a while a customer will ask us why they should purchase our metal snow retention rather than the plastic ones they see. We typically don’t like plastic snow guards for many reasons.

The first reason is because of the type of adhesive used to attach plastic snow guards. Through our testing, we have found that failure exists when freeze-thaw temperature is introduced to the adhesive.
The second reason, they crack and deteriorate when continuously exposed to the sun’s ultraviolet light (UV). See the images below.
 
The third reason, manufacturers don’t warranty failure when the plastic snow guards pull apart from the adhesive.
From all of these reasons this why metal snow retention is a much wiser choice!

 

plastic vs TRA

TRA Metal Clamp-on vs Plastic Guards

 

Most plastics eventually become brittle when exposed to the sun.

Because of its tough nature, metal can withstand the sun’s destructive UV rays. Over time plastic will crack and deteriorate when continuously exposed to the sun.

                        plastic-snow-guards-park-valley-school-9plastic-snow-guards-park-valley-school-8

Cracked, Brittle and Broken “Plastic Snow Guards”

 

TRA’s metal snow retention systems are attached securely using a variety of durable and strong mechanical methods.

Unlike metal, plastic snow guards are usually attached to a roof using caulking, which is likely to fail for the following reasons:

  • If the roof is dirty or wet when installing this makes the adhesive not adhere properly. When have you ever seen a truly clean roof?
  • More common than not snow guards are installed at temperatures below 40 degrees.
  • Caulking cure time can be more than 30 days above 40 degrees.
  •  Over time plastic will crack & deteriorate when continuously exposed to the sun UV.

 

1 rail snow guard for metal roof

TRA C21Z Clamp-on with Ice Flags 

 

Unlike plastic, metal lasts.

Plastic snow retention manufacturers generally do not warranty the attachment just plastic snow guard. If a plastic snow guard fails, the architect or contractor becomes liable for the damage to property /or human life.

Next time you are near a roof with plastic snow guards, see if any are missing and let us know!

We recommend only metal snow retention because we know it can properly protect those in and around your home. For extra protection, we engineer from the sheathing up with the fastener and provide a warranty on the entire snow retention system. Before installation, we engineer a specific layout to see that the system is exactly what you need for your specific location and weather. Contact us with any of your project details and we’ll provide you with the best snow defense system that’ll get you ready for winter.

 

Featured Spotlight “Snow Retention – D Bracket”

 Snow Bracket D

Snow Bracket™ D

A question once asked – On the roofs of many houses, along the eave, there are…best as I can describe it… shaped thingies. I’ve seen others that look octagonal and yet others that are round. I’ve seen them on steep roofs and not-so-steep roofs. My bank even has them. They look great, but do they do anything? 

The answer is yes. What you’re talking about are called snow guards for retaining snow on the roof. When snow and ice accumulate on the roof, they are pulled by gravity and want to slide down the slope of the roof. A well-designed snow retention system is intended to hold the snow on the roof so that it can melt in place.

At TRA Snow and Sun, we engineer and manufacture over 54+ variations of snow guards, and always welcome custom pieces made just for your roofing project. Yes, 54 may seem a lot, right? And your right it is, and here’s why – every roof design can be complex and is different from material, slope, shape, size, pitch, valleys, etc.., and ground snow loads vary significantly from one area to another. This is why we make several different engineered (from the fail point of the system) snow guards tailored to each unique roof designs for every roof type, new or existing, and in many styles that differ in form and function.

trasnowandsun, snow retention, solar mounting systemsSecure Attachment

trasnowandsun, snow retention, solar mounting systemsSuperior Strength

trasnowandsun, snow retention, solar mounting systemsVariety of Material Types

 

snow clips, snow guards, snow bracket

Our first featured spotlight for this month is our unique Snow Guard Bracket D. The Snow Bracket™ D, a permanent snow retention system that is aesthetically pleasing on asphalt shingle roofs. Choose between a vast array of painted powdered colors, available in standard mill finish of steel, copper or aluminum. The Snow Guard Bracket D fastens to roof sheathing to any new construction of an asphalt shingled roof.

Asphalt shingle roofs very common in the United States and it is important you have a Snow Bracket™ that fits the roof type you are installing the product one.

  Snow Bracket™ D

snow bracket d snow guardSnow-Bracket-D Maple-leafSnow-Bracket-D Sunburst

 

Dimensions

Length: 10″
Width: 1 3/16″
Height: 3″

Materials

• Paintlok Steel: 16 ga
• Copper: 48 oz (ASTM B152)
• Stainless Steel: 16 ga (ASTM A240)

 

Colors/Finishes

• Zinc Plated
• Powder coating available in many Colors

*We can provide Paintlock brackets unpainted BUT they must be painted before installing or rusting will occur. Also, available with attachments see images to the left with Maple & Sunburst.

Custom Designs and Engineering

At TRA Snow and Sun, we engineer and lay out each project free of charge using many factors specific to your roof. We then provide you with the snow retention plan, layout and product detail. TRA Snow and Sun representatives will work with you to design the most efficient snow retention system. Fill out our Snow Retention Checklist to get started.

Testing

All Snow Brackets have been tested from the fail point of the system.

Retro-fit Snow Retention. What to do?

One of my older relatives used to say, when confronted with a dilemma, “What to do, what to do….”  It made me chuckle!

But, this phrase describes a dilemma for people confronted with snow and ice avalanching off their already installed roof.  They want to keep the snow up there

snow clips, snow guards, snow bracket

rather than down there

Snow Avalanche Off A RoofFalling Snow in Park City, UT

but what is the best solution?

First of all, retrofit is similar as well as different from new construction.  Basic questions need to be answered for new and retrofit construction.

  • What is the slope?
  • What is the snowload in the area?
  • What type of roofing product is being used?
  • What type of sheathing is under the roofing material?

For retrofit, snow retention installers don’t have the luxury of applying the snow retention devices as the roofing material is installed in a new project.  This is when “What to do, what to do…” might be heard under their breath!

How do you keep snow and ice from falling off while also maintaining a water-tight system when the roofing is already on the roof?  How hard is it to do this?

Contractors need a simple and effective solution.

For asphalt shingles, simulated shake, and other similar roofs, using TRA’s H Snow Bracket, there is no need to pull back the headlap to install a device. Butyl or caulking can be applied on the surface of the roofing product, then the bracket is installed directly into the sheathing using screws.  A clip is then placed over the screws.

Snow-Bracket-H-Short

Snow Bracket H

Easy.  Effective.

The reason this system will work on retrofit is because TRA’s engineering is done using the specific factors as mentioned above.  When installed using the engineered layout, the roof will now hold back the snow and ice that would have fallen off, damaging people or property below.

At TRA Snow and Sun, we help you find an Engineered Solution.  Call us for a free layout, provided within 2 working days.

Snow Bracket H

Designed for most roof types

Available with or without fastener cover clip

Can be powder-coated to match roofing material

Available in 16 g steel, 48 oz copper, 26 g Cor-Ten, 16 ga stainless steel, .063″ aluminum

Finishes – Electro-galvanized, hot-dipped galvanized, mill finish aluminum, copper or Cor-Ten

Power-coating available in many colors.

When Strength Really Matters

snow falling on carsIce_dam_slate_roof

Keeping snow and ice from avalanching off a roof requires a system of superior strength.  When strength really does matter to save lives and prevent damage to property, how does a home or business owner know what snow retention product is strong enough?

How does someone decide what product measures up?

How does one decide the best method of installing a safe and reliable roof snow retention system?

If your answer to these questions is, “I can find that out.  I’ll just look it up online under building codes or ask my roofing contractor.” 

Well, good luck.

There are NO codes for roof snow retention!  None.  Nil.  Nada.  (Our owner, Terry Anderson, is serving on a committee right now to finally establish standards.  Watch for updates on this in the future!)  If a contractor starts sitting codes or standards, be wary.  The contractor might have his own standards, and we sure hope they all do, but there are no national or international standards for snow retention.

This makes it very important for owners, architects, engineers, and contractors to take extra care when designing a snow retention system. At TRA Snow & Sun, we seek to offer high-quality snow retention devices ENGINEERED for the unique snow & ice and building conditions relative to each specific project.

Snow retention as a science has emerged as a technological know-how for human safety. The laws of physics have to be used when holding back lots of destructive snow and ice. Annual assets and personal damage from destructive sliding snow and ice is in the millions, however, the price of a human life is incalculable.  If someone dies as a result of no snow retention or faulty snow retention, the liability threat to household owners and business proprietors is astronomical.

By retaining snow on the roof of a building and allowing even snow melt-off, injuries to residents/guests and property below the roof of a building can be avoided, saving money and limiting the possibility of personal loss. By installing snow retention you can:

  • Prevent danger to residents and guests.
  • Prevent costly roof and property damage.
  • Maintain safe access, keeping entrances/walkways free of snow and ice.
  • Promote energy efficiency by retaining snow which is a good insulation blanket.
  • Trust in the best with the highest quality snow retention devices.

How does one avoid the potential pitfalls to a bad snow retention product?

It can get perplexing with several hundreds of different snow guard types and designs to consider from. With a TRA snow retention system, you know you’re safe because we have gone through extensive product testing. Our products are built to last to the fail point of the snow retention system, not just the product. Unlike other plastic type snow guards that turn yellow and fail over time, TRA’s snow retention systems are superior in strength. Our superior snow retention is designed to manage snow migration on any type of roofing is made of stainless steel or brass.

plastic vs TRA

TRA CLAMP-ON SNOW FENCE vs PLASTIC GLUE-ON SNOW GUARDS

 

In simple terms, a first-rate snow retention product coupled with a reliable and safe FREE engineered spacing layout will help lessen the legal responsibility related to the unexpected slid of snow and ice from roofs. All requesting clients can receive free engineered layouts within 2 working days for each project’s specific requirements. For a free layout, data sheets, specs & quote contact us at 855-542-1861.

 

The Vandelay Project

Snow Retention Case Study – Providing Engineered Snow Retention Solutions for HALF THE COST!

TRA Snow and Sun solves problems!  It’s not just our motto to provide Engineered Solutions.  We really DO IT!

On an addition to a home in Northwest Montana with a high snow load (100 psf); how do you retain snow on a cedar shake roof with a 12/12 pitch, whilst keeping it economical, aesthetically pleasing, and in line with the existing design?

After reviewing their options, Vandelay Construction was ready to order from a competitor, but was concerned about the high cost of the snow retention system, so they did one last internet search of roof snow retention.  They found a project with TRA Snow and Sun snow retention in Bozeman, Montana, liked our product and designs, and contacted us.

Using the information the contractor provided to us, we increased the thickness of the copper from the standard ¼” to 3/8” and designed a 3 rail snow retention system (D3H Deck Mount Snow Fence) specific to the project – cedar shake, 12/12 slope, copper, attaching to 16” OC rafters.  Copper was used to match the decorative end caps on the heavy timbers in the construction of the building.

Not only did the homeowners get a beautiful, warrantied system, but OUR SYSTEM WAS HALF THE COST OF OUR COMPETITORS.

We love the result.  See for yourself.

DSCN2200DSCN2199IMG_0281

DSCN2219DSCN2218DSCN2215

At TRA, we provide Engineered Solutions to all kinds of problems.  Let us help you with your snow retention needs!

Should Your Building Have Snow Retention Devices?

The Tell-Tale Signs in Spring That You Should Install Snow Retention

C-2-2-Z-Snow-Fence-installed-at-a-Government-Camp-in-2

The winter is slowly fading into Spring, but as the snow and ice melts off your roof, there might be some signs that you need snow retention:

Are you noticing large pieces coming off in big chunks?

Do you hear it slipping? (This can be pretty loud and frightening when it happens unexpectedly!)

Are pieces of your gutter coming off due to ice tearing it off as it slipped off your roof?

Are there high spots of snow and ice piled at the eave line on the ground? This might mean that snow or ice has come off that place during the winter.

If you answered yes to any of these questions, continue reading.

People die due to snow and ice sliding off roofs. This is extremely tragic and often avoidable. Use roof snow retention for these reasons:

  1.  Damage/Injury – People and property can be struck by snow and ice falling from the roof. Property damage and injuries, even deaths can occur when snow is not properly retained on a roof.
  2.  Limited Access – Entrances to buildings can be blocked by snow and ice that falls from a roof.
  3.  Roof Damage – When snow and ice masses slide off a roof, costly damage occurs.

Damage from Slidding Snow & Ice

It is especially important to install snow retention above:

  • entryways
  • walkways
  • gathering spots
  • parking lots
  • drive-through areas
  • expensive landscaping
  • ground mounted mechanical
  • roof protrusions such as plumbing vents

Can Your Building Support the Weight of Snow Retention?

You might wonder if your roof can support the weight of snow and ice staying on the roof. If your home is less than 40 years old, the answer is probably yes.

During the 1970-80’s, most states adopted building codes that required structures to support the weight of the building materials (dead load) and the weight of the snow, ice, water, people, etc. (live load). By the year 2000, international building codes were universally adopted with similar standards. So, if the structure was built post 1975, you are unlikely to have any structural problems when keeping snow on the roof (it also helps insulate your roof, saving heating costs!).

Snow Retention – The Invisible Code

Snow retention codes do not seem to be a priority in the United States’ roofing industry. But it is very common to see snow and ice sliding off of a metal roof’s slippery surface. Snow and ice crushes cars, and damages the roof, gutters, and landscape.  In some cases, snow and ice cascading off roofs has killed people. Codes for snow retention systems are essential to protect people and property from sliding ice and snow.

There are many reasons snow retention systems fail and why we need codes in place.  Some examples are:

PRODUCT FAILURE

snow retention system

This snow retention system was not engineered for some variable of the project that caused it to fail.

The snow guard was not strong enough to hold the load it was carrying.

Anyone can cast a wax snow guard, spread some adhesive on the bottom, and tell the consumer how to install it without any testing of the product or the system. Codes would provide a standard to ensure adequately designed products are utilized.

SHEATHING/ROOFING MATERIAL FAILURE

Roofing material is inadequately secured for the shear created by sliding snow.

If the roofing material is not securely fastened to the deck (specifically on standing seam metal roofs), added weight can cause the standing seam metal roof to slide right off, along with the rest of the roofing material and snow retention system. There is a code requirement in place for wind uplift on standing seam metal roofs, but not for shear strength.

Screws or fasteners pull out.

sliding snow and ice

Sliding snow can be incredibly dangerous.

When installing snow retention on roof sheathing, the thickness and type of the sheathing determines the fastener pull-out strength.  If one is installing a snow retention system on 7/16-in. OSB board, the fastener will fail more quickly than when using ¾-in. plywood.  (See chart below.) When designing a layout for a project, many snow retention manufacturers do not test for these variations.  If the snow retention system was designed for ¾-in. plywood and the project is using 7/16-in. OSB board, the whole system needs to be redesigned.

The fastener does not penetrate the sheathing.

If the fastener/screw is not penetrating the sheathing, the snow guard will not have the holding strength for which it was designed.

 

 

ADHESIVE FAILURE

plastic snow guards

These plastic snow guards fell to the ground because the adhesive did not bond properly

When using an adhesive, if the surface is not free of dust, dirt, oil, or waterproofing; or it is not clean and dry, the adhesive will not adhere properly.
If the temperature is not above 50 degrees F, the sealant will not cure. If a load is placed on the snow guard before the 28-day cure time, the snow guard is more likely to fail. (This is according to the Technical Data Sheet  for SB-190)

SYSTEM FAILURE

The system is not designed for the roof slope and snow load.

When designing a snow retention system, factors change from project to project: the slope, roof type, sheathing type, and roof snow load.  If the snow retention system is not engineered for the variables of the project, it can fail.
Most snow guards are not tested to the fail point of the system.

Many snow guard manufacturers claim theirs are tested, and many of them are, but they are not tested to the fail point of the entire system.  The product may be tested to maintain its shape, but was it tested to stay on the roof?  It’s great if the product stays in one piece, but not if the fastener fails, the adhesive fails, and the sheathing fails.

snow retention code

A snow retention code needs to be put in place to help prevent injury to people and damage to property.

INSTALLATION FAILURE

The product was not installed to manufacturer’s specifications.

The manufacturer’s instructions need to be followed meticulously in order to ensure safety and to keep warrantees in effect.  Many manufacturers have specific torque requirements, placement, and maintenance instructions.  If these instructions are not followed, the system can fail and the manufacturer is not at fault.

Obviously, there are valid reasons why the United States should establish codes for snow retention on roofs.  Why hasn’t this happened?  A few reasons could be:

  1. Snowfall occurs in certain areas of the country but not nationwide; therefore, the demand for codes is minimal.
  2. Not many deaths occur due to ice and snow sliding.
  3. Property damage is localized.
  4. The insurance industry is not pushing for this type of code.

There are many other codes in place to protect people and property; so why not for snow retention?  We have codes for wind uplift and ICC test standards for product failures due to wind and moisture penetrations, to name a few.  How many life threatening events need to occur before we do the right thing when it comes to a code for snow retention on roofs?

It’s time to make the invisible snow retention code visible.

References

  1. Surebond Technical Data Sheet SB-190.

About the author

Terry E. Anderson has been in the roofing industry for over 35 years. He is the owner of Anderson Associates Consulting and president of T.R.A.-MAGE, Inc., a manufacturer of roof snow and sun accessories. Anderson was sought after to solve tile roof problems, eventually researching solutions to the frequent structural damage caused by sliding snow and ice. Traveling to Europe, Terry studied how the roofing industry there successfully dealt with snow and ice issues. Using his years of experience and research, he coauthored Concrete and Clay Tile Roof Design Criteria for Cold and Snow Regions. Anderson founded T.R.A. Snow and Sun, now in partnership with MAGE and known as T.R.A.-MAGE, and is recognized as a leader in snow retention systems. He is a member of RCI, WSRCA, and on the technical committee for the Tile Roofing Institute (TRI).

Published: Interface Dec 2011

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