4440-366Y MINNESOTA RUBBER QUAD RING

Part number HQ4440 is an AS568-440 black Buna-N (Nitrile) 70 Shore A Quad-Ring with an inside diameter of 6.725 in (170.82 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 7.275 in (184.79 mm). A quad-ring seats in a standard o-ring gland while offering improved dynamic performance.

Buna-N (Nitrile) is known for low compression set under sustained load, reliable performance in both static and dynamic service. The material holds up against propane and butane, water, and many alcohols. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving automotive brake fluid or strong acids call for a different compound. The profile itself contributes two sealing bands per contact face rather than one and resistance to the spiral twisting that defeats round-section rings.

It sees regular use in fluid power, general industrial maintenance, and hydraulic and pneumatic systems.

This item is sold individually under part number HQ4440. Nominal inside diameter is listed as 6 3/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.