2103-427 PTFE S/T BUP FDA

PTFE Back-Up Ring, 4.725 in ID x 0.275 CS, 55D, White, -65 to 500°F

Status
Out of Stock
Est. Ship Date
29 Oct 2026
Material
PTFE (Polytetrafluoroethylene)
Dash Size
427
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
1/4 inch
Nominal Inside Diameter
4 3/4 inch
Nominal Outside Diameter
5 1/4 inch
Unit of Measure
EA
SKU:
TST427

Product Specification

-
This back-up ring is supplied in AS568-427 white PTFE (Teflon) 55 Shore D built to an inside diameter of 4.725 in (120.02 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 5.275 in (133.99 mm), catalogued under part number TST427. It extends o-ring service life by supporting the seal against extrusion under high pressure.

PTFE (Teflon) is specified here for excellent dielectric properties and near-universal chemical inertness. It resists solvents, strong acids and bases, and steam. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Exposure to molten alkali metals or service requiring elastic recovery will shorten service life.

Typical settings include chemical processing, food and beverage, and aggressive-media pipelines.

Stocked as TST427 and sold individually. Nominal inside diameter is listed as 4 3/4 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Item
TST427
Description
2103-427 PTFE S/T BUP FDA
Actual Cross Section
0.275 inch (6.99 mm)
Actual Inside Diameter
4.725 inch (120.02 mm)
Actual Outside Diameter
5.275 inch (133.99 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings