... like NBR, HNBR, SI, Viton, FKM, ect.will be available for NSF o-ring Rubber O-Ring1. Offer a wide range ... , DVGW, FDA and ROHS approved.4. Various materials and hardness for your option, including Buna-N (NBR), HNBR, VITON, Silicone, FluoroSilicone ... sets of 'O' rings and other seals for the refurbishment of specific equipment - and custom-brand them for you. rubber o-ring for sanitary