**2103-264 PTFE S/T BUP FDA

Part number TST264 is an AS568-264 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 7.484 in (190.09 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 7.762 in (197.15 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 for near-universal chemical inertness and a very wide continuous service temperature range. It resists oxidizing media, steam, and strong acids and bases. 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 chemical processing, aggressive-media pipelines, and food and beverage.

Stocked as TST264 and sold individually. Nominal inside diameter is listed as 7 1/2 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.