... O RING ASSORTMENT 70 Durometer Acrylonitrile Butadiene Rubber (Buna-N) Each kit contains these quantities ... Rubber (NR), Styrene Butadiene Rubber (SBR), Butadiene Rubber (BR), Nitrile Rubber (NBR), Ethylene-Proyene Diene Monomer (EPDM), Butyl Rubber (IIR), Chloroprene Rubber (CR), Silicone Rubber, Fluorocarbon Rubber ... OEM orders are acceptable. Metric 70 Durometer Nitrile (Buna-N) Kit 80pc o ring kit