**2103-254 PTFE S/T BUP FDA

This back-up ring is supplied in AS568-254 white PTFE (Teflon) 55 Shore D with an inside diameter of 5.484 in (139.29 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.762 in (146.35 mm), catalogued under part number TST254. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

The compound resists nearly all industrial chemicals, oxidizing media, and strong acids and bases. That behavior comes from the compound itself: PTFE (Teflon) is known for excellent dielectric properties and non-stick, non-contaminating surface characteristics. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. It is not the right choice where molten alkali metals or service requiring elastic recovery are present.

It sees regular use in food and beverage, pharmaceutical and biotech, and laboratory equipment.

Reference part number TST254 when ordering; the item is sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application.