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3M Electrical B258 2.36 x 5.12 x 7.87 Inch Maroon Fire Barrier Block

Manufacturer: 3M | Catalog # B258 | Codale Part # 4134072

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General Product Info

Product UPC
Codale Part No.
  • Installation requires no special tools
  • Pre-formed foam block maintains tight firestop seal to prevent fire, smoke and toxic gas transmission
  • No cure time means faster completion
  • Block is paintable with primer
  • Can be sealed with 3M™ Fire Barrier Rated Foam FIP 1-Step and other 3M™ fire barrier sealants (sold separately)
  • Firestop tested in accordance with ASTM E 814/UL 1479
  • Fits medium to large openings in wall and floor through-penetrations
  • Can be repaired and reused as needed, saving time and labor
Recommended Applications
  • Cable trays
  • Blank openings
  • Insulated pipes, combination penetrations
  • Cables
  • Metal pipes
  • 3M™ B258 Fire Barrier Blocks are firestop tested to the criteria of ASTM E 814/UL 1479 Standard Test Method for Fire Tests of Penetration Firestop Systems, ASTM E 84/UL 273 Standard Test Method for Surface Burning Characteristics of Building Materials, ASTM E 90 Standard Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements, and ASTM E 413 Classification for Rating Sound Insulation.
  • Our 3M™ Fire Barrier Block B258 is a pre-formed foam block designed for easy installation to effectively seal larger openings against smoke, toxic gas and flame. It is simple to use and helps reduce sound transmission.
  • The blocks are fully re-enterable and reusable, saving time and money, while minimizing waste. Once the opening is filled, seal around the perimeter and any penetrating items with 3M™ Fire Barrier Rated Foam FIP 1-Step or other 3M™ fire barrier sealants (sold separately).
  • Effective and easy to install, 3M™ Fire Barrier Block B258 are part of our family of fire protection products that offer the broadest, long-lasting solutions for a variety of commercial, industrial and residential applications. As a trusted leader in the fire protection industry, 3M offers a broad line of affordable products designed to meet the most demanding firestop requirements. Find the solution you need from the industry-preferred line of fire protection products.
  • When sealing larger cavities, use 3M™ Fire Barrier Block B258 to restore the integrity of the wall with a simple "stack, seal, and done" application, without the use of special tools. The blocks are engineered to remain securely in place, eliminating traditional wire mesh reinforcements. Pre-formed blocks help technicians fill large openings quickly . The material is easy to trim on site without special tools, achieving a tight, custom fit. No cure time is required, which means installation is completed faster, and the blocks are paintable with primer for a more seamless appearance.