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378 PTFE SOLID BACKUP RING FDA

PTFE Back-Up Ring, 10.475 in ID x 0.21 CS, 55D, White, -65 to 500°F

Status
Out of Stock
Est. Ship Date
20 Oct 2026
Material
PTFE (Polytetrafluoroethylene)
Dash Size
378
Durometer
55 Shore D
Cross Section Type
Round
Color
White
Minimum Temperature
-65°F (-53.9°C)
Maximum Temperature
500°F (260°C)
Nominal Cross Section
3/16 inch
Nominal Inside Diameter
10 1/2 inch
Nominal Outside Diameter
10 7/8 inch
Unit of Measure
EA
SKU:
TST378SO

Product Specification

-
The TST378SO is an AS568-378 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 10.475 in (266.07 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 10.895 in (276.73 mm). This back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

The material holds up against nearly all industrial chemicals, oxidizing media, and strong acids and bases. PTFE (Teflon) is valued for excellent dielectric properties and near-universal chemical inertness. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Verify compatibility before use with molten alkali metals or elemental fluorine at temperature.

Common environments for this compound include aggressive-media pipelines, semiconductor fabrication, and chemical processing.

TST378SO ships individually. Nominal inside diameter is listed as 10 1/2 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Item
TST378SO
Description
378 PTFE SOLID BACKUP RING FDA
Actual Cross Section
0.21 inch (5.33 mm)
Actual Inside Diameter
10.475 inch (266.07 mm)
Actual Outside Diameter
10.895 inch (276.73 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings