8-215 BLACK BUNA 90D BACK-UP RING

HB90215 is an AS568-215 black Buna-N (Nitrile) 90 Shore A Back-Up Ring built to an inside diameter of 1.046 in (26.57 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.324 in (33.63 mm). In service, this back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

This material stands up to many alcohols, petroleum-based oils, and water. That behavior comes from the compound itself: Buna-N (Nitrile) is valued for strong abrasion and tear resistance, an economical choice for high-volume maintenance programs. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C).

Common environments for this compound include automotive, hydraulic and pneumatic systems, and agricultural equipment.

This item is sold individually under part number HB90215. Unit weight is approximately 0.436 g and nominal inside diameter is listed as 1 1/16 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.