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3M Firestop Block B258, 12 PK, Maroon, 5.12 in W, 2 hr Fire Rating - Firestop Plugs & Blocks
3MFirestop Plugs & Blocks

3M Firestop Block B258, 12 PK, Maroon, 5.12 in W, 2 hr Fire Rating

The 3M Firestop Block (MPN B258) is a maroon firestop plug and block, 8 inches long and 5.12 inches wide, with a 2-hour fire rating, sold in a 12-pack. This 3M product provides a passive fire protection solution for…

SKU 3G-OTH-552164

Also listed as: B 258 · B-258

Brand
3M
Item
Firestop Block B258, 12 PK, Maroon, 5.12 in W, 2 hr Fire Rating
Category
Firestop Plugs & Blocks
Available to Order
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Local availability & support

Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

3M
Manufacturer Part Number
B258
Type
12 PK
Color
Maroon
Overall Wd
5.12 in
Fire Rating
2 hr

Technical Documents

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3M Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The 3M Firestop Block (MPN B258) is a maroon firestop plug and block, 8 inches long and 5.12 inches wide, with a 2-hour fire rating, sold in a 12-pack. This 3M product provides a passive fire protection solution for sealing penetrations in fire-rated assemblies.

Frequently Asked Questions

What is the 3M Firestop Block used for?

The 3M Firestop Block (B258) is a passive fire protection device used to seal cable trays, conduit, and pipe penetrations in fire-rated walls and floors. It maintains the fire-resistance rating of the assembly, preventing the spread of flames and smoke during a fire.

What are the specifications of the 3M Firestop Block B258?

The 3M Firestop Block B258 is maroon, 8 inches long and 5.12 inches wide, with a 2-hour fire rating. It comes in a 12-pack. This 3M product is designed for use in fire-rated assemblies to seal penetrations and maintain compartmentation.

Where to buy 3M Firestop Blocks worldwide?

3G Electric supplies the 3M Firestop Block B258 to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this 12-pack of firestop blocks.

How to install 3M Firestop Blocks?

Install 3M Firestop Blocks by placing them tightly around cables or pipes within the penetration opening. Ensure the block fully fills the gap and is flush with the wall surface. Follow the manufacturer's instructions for stacking and sealing multiple blocks to maintain the 2-hour fire rating.

Used in

Common applications for 3M
Industrial process water filtration — 3M solid polypropylene cartridge (e.g., RT10Q16G20NN, 7 micron) for sediment removal in manufacturing lines.
Cooling tower pre-treatment — 3M string-wound cartridge (e.g., RT39B16G20NN, 30 micron) to protect heat exchangers from particulate fouling.
Food and beverage rinse water — 3M 1 micron solid cartridge (RT10Y16G20NN) for fine filtration to meet quality standards.
Chemical processing feed water — 3M 27 micron solid cartridge (RT30L16G20NN) for high-flow sediment reduction upstream of sensitive equipment.
Wastewater effluent polishing — 3M 2 micron string-wound cartridge (RT09Y16G20NN) for final particulate removal before discharge or reuse.
Pharmaceutical utility water — 3M 0 micron string-wound cartridge (RT09L16G20NN) for sub-micron filtration in critical systems.

3M Products

3G Electric supplies 3M firestop plugs & blocks. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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