-421 BLACK BUNA 50D O-RING

APG stocks the H50421, an AS568-421 black Buna-N (Nitrile) 50 Shore A O-Ring measuring an inside diameter of 3.975 in (100.97 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 4.525 in (114.94 mm). An o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

Buna-N (Nitrile) delivers the most widely specified general-purpose sealing elastomer and an economical choice for high-volume maintenance programs. The compound resists water, hydraulic fluids, and many alcohols. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with ketones or polar solvents.

Typical settings include agricultural equipment, hydraulic and pneumatic systems, and general industrial maintenance.

Stocked as H50421 and sold individually. Nominal inside diameter is listed as 4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.