BOSS® 338 Flexible Gun Foam - 24 oz

  • Brand Name: Boss®
  • Sku Number: 481004
  • Unit of Measure: CN
  • Availability: loading

Product Description

BOSS® 338 is a premium, easy-to-use polyurethane foam designed for homeowners, DIYers, and small contractors who need a reliable sealant that performs in tough conditions. It’s a one-component, moisture-curing foam that offers low expansion and high flexibility, making it ideal for projects where movement or shifting might occur—like around windows, doors, or wall joints.

Unlike standard foams, BOSS® 338 won’t crack or lose its seal over time. It moves with your structure, maintaining excellent thermal insulation and soundproofing for years. Plus, it’s environmentally friendly with CFC-free propellants that won’t harm the ozone layer.

With minimal expansion (less than 50%), you get better control, less waste, and a cleaner finish. Whether you're tackling a remodel, weatherproofing your home, or sealing up a new install, BOSS® 338 gets the job done—quickly, cleanly, and permanently.

MPN: 33824
Application:  Window and Door
  • Very high elastic recovery
  • Copes with extreme mechanical movement without cracking
  • Excellent adhesion on most substrates (except Teflon, PE, and PP)
  • High thermal and acoustical insulation performance
  • Very good filling capabilities
  • Excellent stability (no shrink or post expansion)
  • Very precise application due to the foam applicator gun system.
  • Low expansion
  • Good compressibility
  • pdfSDS https://www.draftstopsupply.com//ASSETS/DOCUMENTS/ITEMS/EN/481004 - SDS.pdf
  • pdfSell Sheet https://www.draftstopsupply.com//ASSETS/DOCUMENTS/ITEMS/EN/481004 - TDS.pdf
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