APG stocks the H50903, an AS568-903 black Buna-N (Nitrile) 50 Shore A O-Ring with an inside diameter of 0.301 in (7.65 mm), a cross section of 0.064 in (1.63 mm), and an outside diameter of 0.429 in (10.9 mm). An o-ring remains the most cost-effective sealing element available for pressurized assemblies.
Buna-N (Nitrile) is specified here for low compression set under sustained load, strong abrasion and tear resistance. It resists water, hydraulic fluids, and greases and lubricants. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C).
Maintenance and OEM teams specify it across general industrial maintenance, agricultural equipment, and fluid power.
Order part number H50903, sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Description -903 BLACK BUNA 50D O-RING
Actual Cross Section 0.064 inch (1.63 mm)
Actual Inside Diameter 0.301 inch (7.65 mm)
Actual Outside Diameter 0.429 inch (10.9 mm)
Measurement System Imperial
Product Category O-Rings - Bulk - Commodity