201 PTFE SOLID BACKUP RING FDA

TST201SO is an AS568-201 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 0.171 in (4.34 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.449 in (11.4 mm). In service, this back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

PTFE (Teflon) is specified here for near-universal chemical inertness and excellent dielectric properties. It resists nearly all industrial chemicals, strong acids and bases, and oxidizing media. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). Exposure to elemental fluorine at temperature or molten alkali metals will shorten service life.

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

Reference part number TST201SO when ordering; the item is sold individually. 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.