-438 BLACK BUNA 70D O-RING

H70438 is an AS568-438 black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 6.225 in (158.12 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.775 in (172.09 mm). In service, this o-ring remains the most cost-effective sealing element available for pressurized assemblies.

It resists greases and lubricants, propane and butane, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) delivers 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). Applications involving automotive brake fluid or polar solvents call for a different compound.

Common environments for this compound include hydraulic and pneumatic systems, construction equipment, and fluid power.

This item is sold individually under part number H70438. Unit weight is approximately 29.6112 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. 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.