8-340 BLACK BUNA 90D BACK-UP RING

Part number HB90340 is an AS568-340 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 3.35 in (85.09 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.77 in (95.76 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

Buna-N (Nitrile) delivers low compression set under sustained load and an economical choice for high-volume maintenance programs. The material holds up against greases and lubricants, petroleum-based oils, and propane and butane. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service.

You will find this material specified across automotive, fluid power, and hydraulic and pneumatic systems.

Reference part number HB90340 when ordering; the item is sold individually. Unit weight is approximately 3.17 g. Review your operating media and conditions against this specification before installation.