China as 568 Standard Black Heat Resistant NBR Small Rubber Seal Hollow O Ring as 568 NBR 70 O-Ring As568 Acid Resistant Flat Oring Seal, Find details about China O Ring, O-Ring from as 568 Standard Black Heat Resistant NBR Small Rubber Seal Hollow O Ring as 568 NBR 70 O-Ring As568 Acid Resistant Flat Oring Seal