2103-349 PTFE S/T BUP FDA

Ordered as TST349, this is an AS568-349 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 4.475 in (113.67 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 4.895 in (124.33 mm). The 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 valued for a very wide continuous service temperature range and excellent dielectric properties. This material stands up to nearly all industrial chemicals, solvents, and steam. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C).

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

TST349 ships individually. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.