4MM CS X 157MM ID BLACK BUNA 70D

Part number H4X157 is a black Buna-N (Nitrile) 70 Shore A O-Ring with an inside diameter of 157 mm (6.181 in), a cross section of 4 mm (0.157 in), and an outside diameter of 165 mm (6.5 in). An o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

As a material, Buna-N (Nitrile) is known for strong abrasion and tear resistance, reliable performance in both static and dynamic service. The material holds up against water, hydraulic fluids, and many alcohols. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C).

Maintenance and OEM teams specify it across agricultural equipment, hydraulic and pneumatic systems, and automotive.

H4X157 ships individually. Unit weight is approximately 8.385 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.