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Sale! BOSS 333 Triple Expanding Foam
BOSS ProductsBOSS 333 Triple Expanding Foam applicationsBOSS 333 Triple Expanding Foam


Conspec Family Business BadgeConspec Warranty BadgeTriple Expanding Foam, Ready to use 12-oz Straw Can

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BOSS – 333 Triple Expanding Foam

BOSS – 333 is a ready-to-use, multi-purpose, polyurethane foam that expands to three times its original volume on contact with air. The expanding action fills holes, cracks and gaps more completely than standard caulks. BOSS® 333 has excellent insulating properties and superb adhesion to virtually all building materials. Meets CA-25-4 and is UL tested to meet ASTME-72.

• Ready to use 12-oz Straw Can
• Easy-to-use, multi-purpose urethane foam
• Triple Expanding, it expands three times its original volume!
• Adheres to all building materials except Teflon, silicone and polyethylene
• Weatherproofs against wind and moisture
• Seals by expanding into gaps, cracks and crevices
• Uses include insulating, sealing and filling gaps around pipes, plumbing fixtures, ductwork and foundations
• UL Classified Tested to ASTM E-84
• Complies with EPA Method 24 and California Air Resource Board Method 310



To view the most recent Technical Data Sheet, please click here.

Weight 16 oz
Dimensions 2.5 x 2.5 x 8 in
Product Size

12-oz Straw Can