... ringSizeCustomized/standard and nonstandardBrand Nameo ring.MaterialNBR,HNBR,EPDM,SILICONE,VITON,FLS,FFPM,PTFETemperatureCommon: 20~50degree centigrade;NBR(-40 ... have 10 years to produce the silicone products ,the quality can be guarantee.OEM and ODM are available2.100% NBR,HNBR, ... EPDM,SILICONE,VITON,NR,FLS,FFPM,PU,PTFE etc silicone material Eco ...