Quattro Seals

Quattro Seals are four-lobed seals with a geometry that provides twice the number of sealing surfaces when compared to that of a standard O-ring.  Thus, damage to any particular lobe will be much less likely to cause seal failure.  Twice the number of sealing surfaces also allows a Quattro Seal to seal at lower pressures and/or less interference than would be feasible with an O-ring.

The four-lobed configuration also creates a more stable seal that reduces spiral twisting in reciprocal applications.  This is because than rather than relying solely on squeeze to achieve a seal like an O-ring, a Quattro Seal employs both squeeze and deflection to affect a seal. Quattro Seals can be used in standard O-ring grooves or used in narrower Quattro Seal specific grooves, since less squeeze results in less compression. 

As a note, the one disadvantage of a Quattro ring is high pressure sealability.  The cross section is much more susceptible to failure, since the lobes don't have any support behind them.

RT/Dygert stocks many different AS568 sized Quattro Seals in either 70 durometer nitrile, or 75 durometer Viton®.