FDP3119 is a closed cell PVC foam with a very low density and force to compress. It is designed to create a watertight seal with a minimal amount of force, conforming to rough or irregular surfaces. To create an adequate seal, the foam must be compressed a minimum of 30% in the final joint (depending on the shape of the gasket as well as the roughness of both surfaces). Once in place the foam will be able to handle normal joint movement due to thermal expansion or environmental forces. FDP3119 is B1 certified (DIN 4102-01, 05/98)