568-205 FKM 75 SQUARE CUT RINGS

APG stocks the SV70205, an AS568-205 black Viton® (FKM) 70 Shore A Square-Cut Ring with an inside diameter of 0.421 in (10.69 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.699 in (17.75 mm). A square-cut ring presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.

As a material, Viton® (FKM) is specified for excellent resistance to compression set and permeation, the industry benchmark where nitrile reaches its thermal limit. The material holds up against chlorinated solvents, petroleum oils and fuels, and aggressive chemicals. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in ketones and esters or low-molecular-weight organic acids. The profile itself contributes simple lathe-cut manufacture at low tooling cost and a flat contact band that spreads sealing load across a wider area. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.

Maintenance and OEM teams specify it across oil and gas, automotive fuel systems, and chemical processing.

Reference part number SV70205 when ordering; the item is sold individually. Nominal inside diameter is listed as 7/16 inch. Review your operating media and conditions against this specification before installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.