-420 BLACK BUNA 90D O-RING

This o-ring is supplied in AS568-420 black Buna-N (Nitrile) 90 Shore A measuring an inside diameter of 3.85 in (97.79 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 4.4 in (111.76 mm), catalogued under part number H90420. It creates a positive seal at flange, piston and rod interfaces without added hardware.

Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, low compression set under sustained load. Expect good resistance to water, many alcohols, and petroleum-based oils. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. It is not the right choice where ketones or polar solvents are present.

Maintenance and OEM teams specify it across general industrial maintenance, automotive, and agricultural equipment.

Reference part number H90420 when ordering; the item is sold individually. Unit weight is approximately 16.5 g and nominal inside diameter is listed as 3 7/8 inch. Check the compound against your process media, pressure and temperature before committing to a design. 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.