-277 BLACK BUNA 90D O-RING

Ordered as H90277, this is an AS568-277 black Buna-N (Nitrile) 90 Shore A O-Ring with an inside diameter of 11.484 in (291.69 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 11.762 in (298.75 mm). The o-ring seats in a machined groove and forms a leak-tight barrier when compressed between two mating surfaces.

Expect good resistance to many alcohols, hydraulic fluids, and petroleum-based oils. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for reliable performance in both static and dynamic service, low compression set under sustained load. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with automotive brake fluid or strong acids.

You will find this material specified across automotive, agricultural equipment, and construction equipment.

Order part number H90277, sold individually. Unit weight is approximately 12.772 g and nominal inside diameter is listed as 11 1/2 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.