5.3MM CS X 128MM ID BLACK BUNA 70D

Part number H5.3X128 is a black Buna-N (Nitrile) 70 Shore A O-Ring with an inside diameter of 128 mm (5.039 in), a cross section of 5.3 mm (0.209 in), and an outside diameter of 138.6 mm (5.46 in). An o-ring remains the most cost-effective sealing element available for pressurized assemblies.

Expect good resistance to hydraulic fluids, propane and butane, and water. That behavior comes from the compound itself: Buna-N (Nitrile) is known for low compression set under sustained load and an economical choice for high-volume maintenance programs. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving automotive brake fluid or polar solvents call for a different compound.

Common environments for this compound include fluid power, hydraulic and pneumatic systems, and general industrial maintenance.

Order part number H5.3X128, sold individually. Unit weight is approximately 11.735 g. As always, verify media compatibility and operating conditions against the requirements of your specific application.