2103-259 PTFE S/T BUP FDA

Ordered as TST259, this is an AS568-259 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 6.234 in (158.34 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 6.512 in (165.4 mm). The back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

PTFE (Teflon) is specified here for very wide continuous service temperature range and non-stick, non-contaminating surface characteristics. Expect good resistance to nearly all industrial chemicals, oxidizing media, and steam. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C).

Typical settings include semiconductor fabrication, pharmaceutical and biotech, and chemical processing.

TST259 ships individually. Nominal inside diameter is listed as 6 1/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.