... service O ring is one of the main products in our factory, it is made from Nitrile(NBR), HNBR ,EPDM ... .Rubber moulding over 2000 setsWorker 150Staff25QC5Main productso rings, gaskets,custom rubber parts.Material Nitrile(NBR), HNBR, EPDM,Silicone, ... Heat resistance,Low and High temperature Resistance, Oil and Fuel Resistance, Animal and Vegetable Oil Resistance, Alcohol Resistance, Acid Resistance, ...