One part, fire rated, intumescent polyurethane joint sealant
Bostik Seal 'N' Flex® 1 is a low modulus, one component, Class-A polyurethane sealant. When cured it will form a tough and flexible seal capable of cyclic expansion and compression movement of 100% (+ 50%) of the original installed joint width.
Where to Use
Substrates & Suitable Materials