... .good flexibility, good elasticity TC valve seal1.Materials: NBR, NR ,EPDM ,SBR ,SR ,CR ,Silicon, etc. 2.Various sizes. 3.Superior quality ... . The material of these products are NBR, NR, EPDM, FKM, SILICON RUBBER, NYLON, PU, CR, SBR, EP, IIR etc TC valve seal