568-391 FKM 75 SQUARE CUT RINGS

The SV70391 is an AS568-391 black Viton® (FKM) 70 Shore A square profile Quad-Ring with an inside diameter of 21.953 in (557.61 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 22.373 in (568.27 mm). This quad-ring uses a four-lobed profile to create two sealing surfaces per side, reducing the squeeze needed to seal.

This material stands up to aromatic hydrocarbons, engine and transmission fluids, and many acids. That behavior comes from the compound itself: Viton® (FKM) is widely chosen for the industry benchmark where nitrile reaches its thermal limit, excellent resistance to compression set and permeation. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Verify compatibility before use with ketones and esters or hot water and steam.

You will find this material specified across semiconductor equipment, chemical processing, and oil and gas.

Stocked as SV70391 and sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.