Buna 70-342-Black-Pk25

This o-ring is supplied in AS568-342 black Buna-N (Nitrile) 70 Shore A measuring an inside diameter of 3.6 in (91.44 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 4.02 in (102.11 mm), catalogued under part number SB-H70342-25. It creates a positive seal at flange, piston and rod interfaces without added hardware. Source specification: 4IDX3.625"ODX.1875"CS.

The compound resists propane and butane, many alcohols, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for reliable performance in both static and dynamic service, strong abrasion and tear resistance. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Exposure to ozone and direct sunlight or polar solvents will shorten service life.

You will find this material specified across construction equipment, agricultural equipment, and fluid power.

Reference part number SB-H70342-25 when ordering; the item is sold by the bag. Nominal inside diameter is listed as 3 5/8 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. For a size or compound outside the standard catalog, APG can quote from a print or sample.