QH70218 is an AS568-218 black Buna-N (Nitrile) 70 Shore A quad profile Quad-Ring built to an inside diameter of 1.234 in (31.34 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.512 in (38.4 mm). In service, this quad-ring delivers lower friction and better sealing stability than a comparable round-section o-ring.
It resists greases and lubricants, propane and butane, and many alcohols. That behavior comes from the compound itself: Buna-N (Nitrile) offers an economical choice for high-volume maintenance programs and the most widely specified general-purpose sealing elastomer. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C). Verify compatibility before use with automotive brake fluid or strong acids.
It sees regular use in automotive, fluid power, and hydraulic and pneumatic systems.
Stocked as QH70218 and sold individually. Unit weight is approximately 1.287 g and nominal inside diameter is listed as 1 1/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.
description Q-218 BUNA 70 Q RING
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 1.234 inch (31.34 mm)
Actual_OD 1.512 inch (38.4 mm)
ProductCode Description O-Rings - Square/Quad - Commodity