In the shape of a doughnut-shaped ring, our Rubber O Rings are mechanical gaskets. These rings are useful for securing two or more pieces together by compressing them into a groove. Loops of round-cross-sectioned elastomer form a seal at the interface between two surfaces. We use Rubber O Rings to prevent fluid or air from escaping, since they are a sealing mechanism. In order to prevent fluid or air from escaping, it is necessary to squeeze the O-Ring between two surfaces.