*Q-385 BUNA 70 Q RING

APG stocks the QH70385, an AS568-385 black Buna-N (Nitrile) 70 Shore A Quad-Ring with an inside diameter of 15.955 in (405.26 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 16.375 in (415.93 mm). A quad-ring uses a four-lobed profile to create two sealing surfaces per side, reducing the squeeze needed to seal.

The material holds up against hydraulic fluids, petroleum-based oils, and water. Buna-N (Nitrile) offers low compression set under sustained load, reliable performance in both static and dynamic service. Service temperature is rated from -40°F (-40°C) through 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 a parting line located away from the sealing surface and lower compressive load required to achieve a seal.

Common environments for this compound include automotive, agricultural equipment, and hydraulic and pneumatic systems.

Stocked as QH70385 and sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. 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.