5.7MM CS X 319.3MM ID BLACK BUNA 70D

The H5.7X319.3 is a black Buna-N (Nitrile) 70 Shore A O-Ring with an inside diameter of 319.3 mm (12.571 in), a cross section of 5.7 mm (0.224 in), and an outside diameter of 330.7 mm (13.02 in). This o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load. This item is further identified as Metric O-RING, JIS G320.

As a material, Buna-N (Nitrile) is valued for an economical choice for high-volume maintenance programs and low compression set under sustained load. The compound resists greases and lubricants, many alcohols, and water. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Exposure to ozone and direct sunlight or polar solvents will shorten service life.

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

H5.7X319.3 ships individually. Application requirements vary, so validate compatibility with your process conditions prior to installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.