568-316 HSN90 DURO ORINGS

Ordered as HSN90316, this is an AS568-316 green HNBR (Hydrogenated Nitrile) 90 Shore A O-Ring built to an inside diameter of 0.85 in (21.59 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.27 in (32.26 mm). The o-ring creates a positive seal at flange, piston and rod interfaces without added hardware.

This material stands up to ozone and weathering, sour gas and amine inhibitors, and heat and oxidation. That behavior comes from the compound itself: HNBR (Hydrogenated Nitrile) is known for long service life in refrigerant and oilfield duty, improved ozone and weathering resistance over standard nitrile. Service temperature is rated from -40°F (-40°C) through 325°F (162.8°C). It should not be specified for service in esters or ketones.

You will find this material specified across engine timing systems, commercial refrigeration, and heavy-duty powertrain.

HSN90316 ships individually. Nominal inside diameter is listed as 7/8 inch. Review your operating media and conditions against this specification before installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.