Buna 70-321-Black-Pk50

Ordered as SB-H70321-50, this is an AS568-321 black Buna-N (Nitrile) 70 Shore A O-Ring measuring an inside diameter of 1.162 in (29.51 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.582 in (40.18 mm). The o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load. The catalog record notes: 0.210CSX1.162"IDX1.582"OD.

The material holds up against hydraulic fluids, greases and lubricants, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) offers the most widely specified general-purpose sealing elastomer, reliable performance in both static and dynamic service. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with automotive brake fluid or polar solvents.

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

This item is sold by the bag under part number SB-H70321-50. Nominal inside diameter is listed as 1 3/16 inch. Check the compound against your process media, pressure and temperature before committing to a design. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.