8-123 BLACK BUNA 90D BACK-UP RING

HB90123 is an AS568-123 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 1.174 in (29.82 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.38 in (35.05 mm). In service, this back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, economical choice for high-volume maintenance programs. Expect good resistance to many alcohols, greases and lubricants, and petroleum-based oils. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C).

You will find this material specified across construction equipment, automotive, and fluid power.

Reference part number HB90123 when ordering; the item is sold individually. Unit weight is approximately 0.3655 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.