-378 BLACK BUNA 90D O-RING

Part number H90378 is an AS568-378 black Buna-N (Nitrile) 90 Shore A O-Ring supplied with an inside diameter of 10.475 in (266.07 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 10.895 in (276.73 mm). An o-ring compresses into its gland to block fluid or gas migration across a joint.

The compound resists greases and lubricants, many alcohols, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for an economical choice for high-volume maintenance programs and the most widely specified general-purpose sealing elastomer. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ozone and direct sunlight or automotive brake fluid are present.

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

This item is sold individually under part number H90378. Unit weight is approximately 24.7 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.