-387 BLACK BUNA 90D O-RING

Ordered as H90387, this is an AS568-387 black Buna-N (Nitrile) 90 Shore A O-Ring built to an inside diameter of 17.955 in (456.06 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 18.375 in (466.73 mm). The o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

The compound resists propane and butane, many alcohols, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) delivers the most widely specified general-purpose sealing elastomer and low compression set under sustained load. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Exposure to ozone and direct sunlight or polar solvents will shorten service life.

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

This item is sold individually under part number H90387. Unit weight is approximately 43.7072 g and nominal inside diameter is listed as 18 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. 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.