8.4MM CS X 299.5MM ID BLACK BUNA 70D

H8.4X299.5 is a black Buna-N (Nitrile) 70 Shore A O-Ring measuring an inside diameter of 299.5 mm (11.791 in), a cross section of 8.4 mm (0.331 in), and an outside diameter of 316.3 mm (12.45 in). In service, this o-ring compresses into its gland to block fluid or gas migration across a joint. The catalog record notes: Metric O-RING, JIS P300.

Expect good resistance to many alcohols, greases and lubricants, and water. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for strong abrasion and tear resistance, the most widely specified general-purpose sealing elastomer. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Exposure to ozone and direct sunlight or polar solvents will shorten service life.

You will find this material specified across hydraulic and pneumatic systems, construction equipment, and agricultural equipment.

Order part number H8.4X299.5, sold individually. Unit weight is approximately 65.054 g. Review your operating media and conditions against this specification before installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.