... NBR and Silicone Any size and color are available O ring features: 1. Material: NBR, silicone, NR, FKM ... , neoprene, etc2. Types of O-Ring: O-type, E-type, U-type, V-type,etc ... Seal, Rubber Oil Seal, Rubber Seal, Rubber Gasket, O-Ring: Black, red, yellow, brown, white, green, violet ... Oil Seal,Rubber Oil Seal, O-Ring, Rubber Seal, Rubber Gasket, Rubber Ring, Sealing Ring, Sealing Gasket.