O-Rings are circular rubber gaskets designed to be seated in a groove and compressed during assembly creating a seal at the interface. O-Rings sizes are designated by a AS568 dash number and available in a wide range of materials. Common stock materials for these size O-Rings range from Aflas®, Ethylene Propylene (EPM, EPDM, EPR), Fluorocarbon (FKM, Viton® Fluorel®), Fluorosilicone, Highly Saturated Nitrile (HSN, HNBR), Neoprene®, Nitrile (Buna-N), Perfluoroelastomers, PTFE (Teflon®), Silicone, Urethane, FEP Encapsulated and more!