-440 BLACK BUNA 50D O-RING

APG stocks the H50440, an AS568-440 black Buna-N (Nitrile) 50 Shore A O-Ring supplied 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). An o-ring seats in a machined groove and forms a leak-tight barrier when compressed between two mating surfaces.

The compound resists greases and lubricants, water, and propane and butane. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for low compression set under sustained load, strong abrasion and tear resistance. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Verify compatibility before use with polar solvents or automotive brake fluid.

It sees regular use in hydraulic and pneumatic systems, fluid power, and automotive.

Order part number H50440, sold individually. Nominal inside diameter is listed as 6 3/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.