*4357-366Y MINNESOTA RUBBER QUAD RING

This quad-ring is supplied in AS568-357 black Buna-N (Nitrile) 70 Shore A with an inside diameter of 5.475 in (139.07 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 5.895 in (149.73 mm), catalogued under part number HQ4357. It delivers lower friction and better sealing stability than a comparable round-section o-ring.

The compound resists propane and butane, many alcohols, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for an economical choice for high-volume maintenance programs and low compression set under sustained load. 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. The profile itself contributes a parting line located away from the sealing surface and resistance to the spiral twisting that defeats round-section rings.

It sees regular use in agricultural equipment, fluid power, and automotive.

Reference part number HQ4357 when ordering; the item is sold individually. Application requirements vary, so validate compatibility with your process conditions prior to 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.