H90138 is an AS568-138 black Buna-N (Nitrile) 90 Shore A O-Ring built to an inside diameter of 2.112 in (53.64 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.318 in (58.88 mm). In service, this o-ring remains the most cost-effective sealing element available for pressurized assemblies.
Buna-N (Nitrile) is known for the most widely specified general-purpose sealing elastomer and low compression set under sustained load. It resists petroleum-based oils, greases and lubricants, and many alcohols. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with ketones or automotive brake fluid.
Maintenance and OEM teams specify it across general industrial maintenance, agricultural equipment, and hydraulic and pneumatic systems.
This item is sold individually under part number H90138. Unit weight is approximately 1.3374 g and nominal inside diameter is listed as 2 1/8 inch. Review your operating media and conditions against this specification before installation. 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.
description -138 BLACK BUNA 90D O-RING
uf_description2 0.103" (2.62MM) CS X 2.112" (53.64MM) ID
Actual_CS 0.103 inch (2.62 mm)
Actual_ID 2.112 inch (53.64 mm)
Actual_OD 2.318 inch (58.88 mm)
ProductCode Description O-Rings - Bulk - Commodity