An O-ring is a circle shaped seal typically used to prevent the passing of air or fluid. Nitrile O-Rings are the most widely used and offer excellent resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohols. Durometer is the measure of the hardness of a material, typically of polymers, elastomers, and rubbers. Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. Lower numbers indicate less resistance and softer materials.

An O-ring is a circle shaped seal typically used to prevent the passing of air or fluid. Viton O-Rings are far superior to Buna-N O-Rings for high temperature applications and are recommended when a seal is needed for temperatures up to 400°F. Durometer is the measure of the hardness of a material, typically of polymers, elastomers, and rubbers. Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. Lower numbers indicate less resistance and softer materials.