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373 PTFE SOLID BACKUP RING FDA

PTFE Back-Up Ring, 8.975 in ID x 0.21 CS, 55D, White, -65 to 500°F

Status
Out of Stock
Est. Ship Date
21 Oct 2026
Material
PTFE (Polytetrafluoroethylene)
Dash Size
373
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
9 inch
Nominal Outside Diameter
9 3/8 inch
Unit of Measure
EA
SKU:
TST373SO

Product Specification

-
Part number TST373SO is an AS568-373 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 8.975 in (227.97 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 9.395 in (238.63 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

PTFE (Teflon) is specified for a very wide continuous service temperature range and near-universal chemical inertness. The compound resists strong acids and bases, oxidizing media, and nearly all industrial chemicals. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Applications involving molten alkali metals or service requiring elastic recovery call for a different compound.

Typical settings include pharmaceutical and biotech, aggressive-media pipelines, and food and beverage.

Order part number TST373SO, sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Item
TST373SO
Description
373 PTFE SOLID BACKUP RING FDA
Actual Cross Section
0.21 inch (5.33 mm)
Actual Inside Diameter
8.975 inch (227.97 mm)
Actual Outside Diameter
9.395 inch (238.63 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings