Discover TF-501 Rigid PU Foam Synergies Fire Retardant Chemicals, an intumescent, environment-friendly flame retardant designed for rigid polyurethane foam. This halogen-free, phosphorus-nitrogen synergies product ensures excellent water resistance, smoke suppression, and high flame retardant efficiency. Perfect for achieving UL-94 V-0 and GB/T 8624-2012 B2 standards.