-390 BLACK BUNA 50D O-RING

Ordered as H50390, this is an AS568-390 black Buna-N (Nitrile) 50 Shore A O-Ring measuring an inside diameter of 20.953 in (532.21 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 21.373 in (542.87 mm). The o-ring creates a positive seal at flange, piston and rod interfaces without added hardware.

The material holds up against hydraulic fluids, propane and butane, and greases and lubricants. Buna-N (Nitrile) is widely chosen for low compression set under sustained load, reliable performance in both static and dynamic service. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving ketones or strong acids call for a different compound.

You will find this material specified across general industrial maintenance, hydraulic and pneumatic systems, and automotive.

Reference part number H50390 when ordering; the item is sold individually. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.