4MM CS X 20MM ID BLACK BUNA 70D

APG stocks the H4X20, a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 20 mm (0.787 in), a cross section of 4 mm (0.157 in), and an outside diameter of 28 mm (1.1 in). An 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 water. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for strong abrasion and tear resistance, the most widely specified general-purpose sealing elastomer. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Applications involving ozone and direct sunlight or strong acids call for a different compound.

Common environments for this compound include automotive, fluid power, and hydraulic and pneumatic systems.

Reference part number H4X20 when ordering; the item is sold individually. Unit weight is approximately 1.218 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. 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.