-309 BLACK BUNA 70D O-RING

Ordered as H70309, this is an AS568-309 black Buna-N (Nitrile) 70 Shore A O-Ring measuring an inside diameter of 0.412 in (10.46 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 0.832 in (21.13 mm). The o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

As a material, Buna-N (Nitrile) delivers low compression set under sustained load, reliable performance in both static and dynamic service. The compound resists greases and lubricants, hydraulic fluids, and petroleum-based oils. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Exposure to strong acids or automotive brake fluid will shorten service life.

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

H70309 ships individually. Unit weight is approximately 1.3517 g and nominal inside diameter is listed as 7/16 inch. 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.