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369 PTFE SOLID BACKUP RING FDA

PTFE Back-Up Ring, 7.975 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
369
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
8 inch
Nominal Outside Diameter
8 3/8 inch
Unit of Measure
EA
SKU:
TST369SO

Product Specification

-
Part number TST369SO is an AS568-369 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 7.975 in (202.57 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 8.395 in (213.23 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

The material holds up against oxidizing media, solvents, and strong acids and bases. That behavior comes from the compound itself: PTFE (Teflon) is valued for near-universal chemical inertness and a very wide continuous service temperature range. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). Exposure to molten alkali metals or elemental fluorine at temperature will shorten service life.

Maintenance and OEM teams specify it across chemical processing, pharmaceutical and biotech, and semiconductor fabrication.

Order part number TST369SO, sold individually. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Item
TST369SO
Description
369 PTFE SOLID BACKUP RING FDA
Actual Cross Section
0.21 inch (5.33 mm)
Actual Inside Diameter
7.975 inch (202.57 mm)
Actual Outside Diameter
8.395 inch (213.23 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings