Q-256 BUNA 70 Q RING

Ordered as QH70256, this is an AS568-256 black Buna-N (Nitrile) 70 Shore A quad profile Quad-Ring built to an inside diameter of 5.734 in (145.64 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 6.012 in (152.7 mm). The quad-ring provides a dual sealing band on each contact face for improved reliability.

The compound resists many alcohols, petroleum-based oils, and water. That behavior comes from the compound itself: Buna-N (Nitrile) delivers low compression set under sustained load, strong abrasion and tear resistance. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with polar solvents or ozone and direct sunlight.

You will find this material specified across hydraulic and pneumatic systems, automotive, and general industrial maintenance.

Reference part number QH70256 when ordering; the item is sold individually. Unit weight is approximately 5.6728 g and nominal inside diameter is listed as 5 3/4 inch. 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.