568-389 BUNA 70 SQUARE CUT RINGS

Ordered as SH70389, this is an AS568-389 black Buna-N (Nitrile) 70 Shore A square profile Quad-Ring measuring an inside diameter of 19.953 in (506.81 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 20.373 in (517.47 mm). The quad-ring uses a four-lobed profile to create two sealing surfaces per side, reducing the squeeze needed to seal.

It resists water, petroleum-based oils, and propane and butane. Buna-N (Nitrile) offers strong abrasion and tear resistance, reliable performance in both static and dynamic service. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ketones or automotive brake fluid are present.

Maintenance and OEM teams specify it across fluid power, agricultural equipment, and construction equipment.

This item is sold individually under part number SH70389. 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.