8-335 BLACK BUNA 90D BACK-UP RING

APG stocks the HB90335, an AS568-335 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 2.725 in (69.22 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.145 in (79.88 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, most widely specified general-purpose sealing elastomer. The material holds up against many alcohols, water, and greases and lubricants. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with ozone and direct sunlight or automotive brake fluid.

It sees regular use in hydraulic and pneumatic systems, general industrial maintenance, and agricultural equipment.

Reference part number HB90335 when ordering; the item is sold individually. Unit weight is approximately 2.4651 g and nominal inside diameter is listed as 2 3/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application.