4339-366Y MINNESOTA RUBBER QUAD RING

APG stocks the HQ4339, an AS568-339 black Buna-N (Nitrile) 70 Shore A Quad-Ring supplied with an inside diameter of 3.225 in (81.92 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.645 in (92.58 mm). A quad-ring resists spiral failure in reciprocating service thanks to its multi-lobe geometry.

Expect good resistance to hydraulic fluids, greases and lubricants, and water. Buna-N (Nitrile) is known for low compression set under sustained load, reliable performance in both static and dynamic service. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where strong acids or ozone and direct sunlight are present. The profile itself contributes resistance to the spiral twisting that defeats round-section rings and lower compressive load required to achieve a seal.

It sees regular use in general industrial maintenance, automotive, and agricultural equipment.

Reference part number HQ4339 when ordering; the item is sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.