*4355-366Y MINNESOTA RUBBER QUAD RING

Part number HQ4355 is an AS568-355 black Buna-N (Nitrile) 70 Shore A Quad-Ring measuring an inside diameter of 5.225 in (132.72 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 5.645 in (143.38 mm). A quad-ring delivers lower friction and better sealing stability than a comparable round-section o-ring.

As a material, Buna-N (Nitrile) is widely chosen for low compression set under sustained load, reliable performance in both static and dynamic service. It resists petroleum-based oils, greases and lubricants, and propane and butane. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Applications involving ozone and direct sunlight or automotive brake fluid call for a different compound. The profile itself contributes two sealing bands per contact face rather than one and lower compressive load required to achieve a seal.

Typical settings include construction equipment, general industrial maintenance, and fluid power.

HQ4355 ships individually. Nominal inside diameter is listed as 5 1/4 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.