4279-366Y MINNESOTA RUBBER QUAD RING

This quad-ring is supplied in AS568-279 black Buna-N (Nitrile) 70 Shore A supplied with an inside diameter of 12.984 in (329.79 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 13.262 in (336.85 mm), catalogued under part number HQ4279. It delivers lower friction and better sealing stability than a comparable round-section o-ring.

Buna-N (Nitrile) is specified for reliable performance in both static and dynamic service, low compression set under sustained load. It resists hydraulic fluids, many alcohols, and greases and lubricants. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in strong acids or automotive brake fluid. The profile itself contributes lower compressive load required to achieve a seal and two sealing bands per contact face rather than one.

You will find this material specified across general industrial maintenance, fluid power, and automotive.

HQ4279 ships individually. Nominal inside diameter is listed as 13 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.