5.7MM CS X 54.2MM ID BLACK BUNA 70D

Part number H5.7X54.2 is a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 54.2 mm (2.134 in), a cross section of 5.7 mm (0.224 in), and an outside diameter of 65.6 mm (2.58 in). An o-ring compresses into its gland to block fluid or gas migration across a joint.

The compound resists water, greases and lubricants, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) is valued for low compression set under sustained load, strong abrasion and tear resistance. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving ozone and direct sunlight or ketones call for a different compound.

Typical settings include agricultural equipment, fluid power, and general industrial maintenance.

Reference part number H5.7X54.2 when ordering; the item is sold individually. Check the compound against your process media, pressure and temperature before committing to a design. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.