568-391 BUNA 90 O RINGS

Item H90391 is a Buna-N NBR 90A O-Ring built for industrial fluid sealing, equipment repair, pumps, valves, cylinders and general maintenance applications. The item is specified by AS568-391; 21.953 inch (557.61 mm) ID x 0.21 inch (5.33 mm) CS; 22.373 inch (568.27 mm) OD, with 22 inch nominal ID; 3/16 inch nominal CS for cross-reference against common gland and replacement dimensions. The Buna-N nitrile (NBR) compound is selected for oil, grease, fuel and general hydraulic fluid resistance in common industrial equipment. It is with a listed temperature range of -40°F (-40°C) to 250°F (121°C), which can help narrow material selection for heat, cold or process exposure. The black color and round profile provide a practical visual identifier during receiving, stocking and installation. This standard industrial O-ring can be used across compatible static and dynamic sealing applications in pumps, valves, cylinders and assemblies. The each-unit format supports precise replacement, kitting, resale and job-specific purchasing. Key selection details include material, hardness, product type, cross-section, inside diameter, outside diameter and application. These specification details help customers and resellers compare the part by performance requirements rather than brand name alone.