Rubber Silicone Stopper 1,FDA,ROHS Certificated. 2,OEM service. 3,Ozone resistance,aging resistance,UV resistance. Rubber Silicone Stopper1, Material:NBR,CR,HNBR,ACM,SBR ... resistance,oil and fuel resistance,weathering resistance,Ozone resistance etc.4, Certification: ISO9001:2008,ROHS,FDA5, Packing: plastic bag&carton box ...