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BOSS - 333 Triple Expanding Foam 24 oz.

Item: BT33316
MFR: 142302

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About This Product

Product Info


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.

  • Air sealing
  • Partition walls with ceilings
  • Through penetrations around cables and pipes
  • Seams between chimneys, roof protection, roof panels andwall panels

  • Meets CA-25-4
  • UL Classified, Tested to ASTM E-84
  • Triple Expanding
  • Weatherproofs against wind and moisture
  • Fills gaps, cracks and holes
  • Seals out insects and pests
  • Can be sanded, painted and stained
  • Complies with EPA Method 24 and CaliforniaAir Resource Board Method 310
  • VOC Compliant


Weight1.83 Pounds (lbs)
Width2.5 Inches (In)
Height11.125 Inches (In)
Country of OriginBEL
Length2.5 Inches (In)
ApplicationFills Holes, Gaps, And Cracks More Completely Than Standard Caulk. Has Excellent Insulating Properties And Superb Adhesion To Virtually All Building Materials.
Application Temperature40°F to 115°F (4.4°C to 46.1°C)
BasePolyurethane foam
CompositionPolyurethane Foam
Coverage41.6 Liters Freely Foamed
Dry Time24 Hours
Fire RatingASTM E-84-04 UL 723 Fire Testing. Flame Spread-10, Smoke Developed-30
Flash Point-21°C
For Use WithWith building materials for weatherproofing
FunctionsFilling Voids
Prop 65No
RatingsFlame Spread - 15; Smoke Developed - 35
Service Temperature-40°F to 200°F (-40°C to 93.3°C)
Shelf Life1 Year from the date of shipment
Size24 Ounce
StandardsCA-25-4, EPA Method 24, CARB Method 310
Storage Temperature>90°F (32.2°C)
Temperature Range-40°F to 200°F (-40°C to 93.3°C)
UL ListedYes
UV ResistantNo
Volume24 fl oz


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