2103-327 PTFE S/T BUP FDA

APG stocks the TST327, an AS568-327 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 1.725 in (43.82 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 2.145 in (54.48 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

The material holds up against solvents, strong acids and bases, and steam. That behavior comes from the compound itself: PTFE (Teflon) is valued for near-universal chemical inertness and excellent dielectric properties. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). Applications involving service requiring elastic recovery or molten alkali metals call for a different compound.

You will find this material specified across food and beverage, laboratory equipment, and aggressive-media pipelines.

This item is sold individually under part number TST327. Nominal inside diameter is listed as 1 3/4 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. 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.