We make available Rectangular Compression Ring with a rectangular cross section. This Rectangular Compression Ring with its geometrically simple shape performs the necessary sealing functions under normal operating conditions. With a peripheral coating and appropriate barrel face the Rectangular Compression Ring is today used mainly in the top groove in passenger car gasoline and diesel engines. Besides, serving in internal combustion engines, Rectangular Compression Ring is commonly used as rotary shaft seals, e.g. transmission seals.