2103-341 PTFE S/T BUP FDA

APG stocks the TST341, an AS568-341 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 3.475 in (88.27 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.895 in (98.93 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

PTFE (Teflon) is specified here for very wide continuous service temperature range and non-stick, non-contaminating surface characteristics. It resists nearly all industrial chemicals, oxidizing media, and solvents. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Verify compatibility before use with elemental fluorine at temperature or service requiring elastic recovery.

Maintenance and OEM teams specify it across aggressive-media pipelines, laboratory equipment, and pharmaceutical and biotech.

Stocked as TST341 and sold individually. Nominal inside diameter is listed as 3 1/2 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.