The TST375 is an AS568-375 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 9.475 in (240.67 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 9.895 in (251.33 mm). This back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
It resists oxidizing media, steam, and strong acids and bases. PTFE (Teflon) is valued for a very wide continuous service temperature range and non-stick, non-contaminating surface characteristics. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C).
You will find this material specified across semiconductor fabrication, chemical processing, and pharmaceutical and biotech.
This item is sold individually under part number TST375. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description 2103-375 PTFE S/T BUP FDA
Actual Cross Section 0.21 inch (5.33 mm)
Actual Inside Diameter 9.475 inch (240.67 mm)
Actual Outside Diameter 9.895 inch (251.33 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings