568-356 BUNA 70 SQUARE CUT RINGS

Part number SH70356 is an AS568-356 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring measuring an inside diameter of 5.35 in (135.89 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 5.77 in (146.56 mm). A square-cut ring offers greater contact area against the gland wall than an equivalent o-ring.

Buna-N (Nitrile) is specified for strong abrasion and tear resistance, reliable performance in both static and dynamic service. This material stands up to propane and butane, hydraulic fluids, and petroleum-based oils. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Exposure to polar solvents or automotive brake fluid will shorten service life. The profile itself contributes a rectangular section that will not roll in the groove and a flat contact band that spreads sealing load across a wider area. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.

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

Stocked as SH70356 and sold individually. Unit weight is approximately 12.12 g. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.