5.3MM CS X 243MM ID BLACK BUNA 70D

Ordered as H5.3X243, this is a black Buna-N (Nitrile) 70 Shore A O-Ring supplied with an inside diameter of 243 mm (9.567 in), a cross section of 5.3 mm (0.209 in), and an outside diameter of 253.6 mm (9.98 in). The o-ring seats in a machined groove and forms a leak-tight barrier when compressed between two mating surfaces.

Buna-N (Nitrile) is specified here for reliable performance in both static and dynamic service, strong abrasion and tear resistance. This material stands up to water, petroleum-based oils, and greases and lubricants. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. It should not be specified for service in ketones or strong acids.

Maintenance and OEM teams specify it across hydraulic and pneumatic systems, general industrial maintenance, and construction equipment.

H5.3X243 ships individually. Unit weight is approximately 21.23 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.