4208-366Y MINNESOTA RUBBER QUAD RING

This quad-ring is supplied in AS568-208 black Buna-N (Nitrile) 70 Shore A supplied with an inside diameter of 0.609 in (15.47 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.887 in (22.53 mm), catalogued under part number HQ4208. It delivers lower friction and better sealing stability than a comparable round-section o-ring.

The material holds up against propane and butane, petroleum-based oils, and greases and lubricants. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for an economical choice for high-volume maintenance programs, strong abrasion and tear resistance. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. The profile itself contributes lower compressive load required to achieve a seal and resistance to the spiral twisting that defeats round-section rings.

Maintenance and OEM teams specify it across general industrial maintenance, hydraulic and pneumatic systems, and automotive.

Reference part number HQ4208 when ordering; the item is sold individually. Nominal inside diameter is listed as 5/8 inch. Review your operating media and conditions against this specification before 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.