QUAD & SQUARE RINGS
A Square-Ring is a sealing device made in the form of a torus, with a square shaped cross-section. It is available in a variety of elastomeric and thermoplastic materials. In most static applications, it is a direct replacement of an O-RING and generally will perform this high pressure gasketing function as well as, or better than an O-RING.
The quad ring is a self-sealing rubber ring with four rounded sealing lobes. Quad rings were primarily designed to replace o-rings in cases where the application of o-rings is not satisfactory or not suitable at all.