1. Material: It is a foam sealing product with rubber as base material which is embedded in the rack. 2. Structure and install form: Inlaid structure,any shape customer need. 3. Volume dilate rate: ?????600% 4. Speciality and function: Dilated to be the rubber sponge elastomer with the paint temperature raised,the volume could be even more than ten times bigger than before,airproof. Make the noise low,and make the passenger comfortable.