2103-039 PTFE S/T BUP FDA

TST039 is an AS568-039 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 2.739 in (69.57 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 2.879 in (73.13 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 very wide continuous service temperature range and one of the lowest coefficients of friction of any solid. Expect good resistance to strong acids and bases, solvents, and steam. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). It is not the right choice where molten alkali metals or elemental fluorine at temperature are present.

It sees regular use in semiconductor fabrication, chemical processing, and food and beverage.

Reference part number TST039 when ordering; the item is sold individually. Nominal inside diameter is listed as 2 3/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.