Check out our large selection of Rubber-O-Rings. The Rubber-O-Rings are sold individually and in packages of 25. Most of our O-Rings are made of EPDM (ethylene propylene diene monomer). EPDM is better because it is more resistant to UV rays. Some O-Rings are made of Buna or NBR rubber. These are usually the ones that are shiny and appear a bit more translucent. Tensile strength and longevity are about the same for both types of rubber. Click here to watch our Rubber-O-Ring Video Tutorial.