568-257 HSN90 DURO ORINGS

APG stocks the HSN90257, an AS568-257 green HNBR (Hydrogenated Nitrile) 90 Shore A O-Ring measuring an inside diameter of 5.859 in (148.82 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 6.137 in (155.88 mm). An o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

The material holds up against petroleum oils and fuels, ozone and weathering, and sour gas and amine inhibitors. That behavior comes from the compound itself: HNBR (Hydrogenated Nitrile) is known for improved ozone and weathering resistance over standard nitrile, the oil resistance of nitrile with substantially better heat capability. Published continuous service range is -40°F (-40°C) to 325°F (162.8°C). It should not be specified for service in chlorinated hydrocarbons or ketones.

Common environments for this compound include heavy-duty powertrain, automotive air conditioning, and engine timing systems.

This item is sold individually under part number HSN90257. Nominal inside diameter is listed as 5 7/8 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application.