-259 BLACK BUNA 90D O-RING

Ordered as H90259, this is an AS568-259 black Buna-N (Nitrile) 90 Shore A O-Ring measuring an inside diameter of 6.234 in (158.34 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 6.512 in (165.4 mm). The o-ring delivers dependable bidirectional sealing in a compact groove envelope.

This material stands up to propane and butane, petroleum-based oils, and greases and lubricants. That behavior comes from the compound itself: Buna-N (Nitrile) offers strong abrasion and tear resistance, an economical choice for high-volume maintenance programs. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where strong acids or ozone and direct sunlight are present.

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

Order part number H90259, sold individually. Unit weight is approximately 7.0289 g and nominal inside diameter is listed as 6 1/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.