8-009 BLACK BUNA 90D BACK-UP RING

Part number HB90009 is an AS568-009 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 0.208 in (5.28 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 0.348 in (8.84 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

Buna-N (Nitrile) is specified here for low compression set under sustained load and economical choice for high-volume maintenance programs. Expect good resistance to petroleum-based oils, water, and greases and lubricants. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C).

Maintenance and OEM teams specify it across general industrial maintenance, agricultural equipment, and construction equipment.

Stocked as HB90009 and sold individually. Unit weight is approximately 0.038 g and nominal inside diameter is listed as 7/32 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.