8-342 BLACK BUNA 90D BACK-UP RING

Part number HB90342 is an AS568-342 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 3.6 in (91.44 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 4.02 in (102.11 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

Buna-N (Nitrile) is specified here for economical choice for high-volume maintenance programs, reliable performance in both static and dynamic service. It resists many alcohols, greases and lubricants, and petroleum-based oils. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in ozone and direct sunlight or automotive brake fluid.

Common environments for this compound include construction equipment, agricultural equipment, and fluid power.

HB90342 ships individually. Unit weight is approximately 3.1967 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.