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8-201 BLACK FKM 90D BACK-UP RING

Viton® Back-Up Ring, 0.171 in ID x 0.139 CS, 90A, Black, -15 to 400°F

Status
Out of Stock
Est. Ship Date
20 Oct 2026
Material
Fluoroelastomer (FKM/Viton)
Dash Size
201
Durometer
90 Shore A
Cross Section Type
Round
Color
Black
Minimum Temperature
-15°F (-26°C)
Maximum Temperature
400°F (204°C)
Nominal Cross Section
1/8 inch
Nominal Inside Diameter
3/16 inch
Nominal Outside Diameter
7/16 inch
Unit of Measure
EA
SKU:
VBU90201

Product Specification

-
Part number VBU90201 is an AS568-201 black Viton® (FKM) 90 Shore A Back-Up Ring supplied with an inside diameter of 0.171 in (4.34 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.449 in (11.4 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

Expect good resistance to engine and transmission fluids, petroleum oils and fuels, and aromatic hydrocarbons. Viton® (FKM) is valued for the industry benchmark where nitrile reaches its thermal limit and long service life in hot, chemically aggressive environments. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Applications involving hot water and steam or ketones and esters call for a different compound.

Common environments for this compound include chemical processing, oil and gas, and aerospace.

Reference part number VBU90201 when ordering; the item is sold individually. Check the compound against your process media, pressure and temperature before committing to a design. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Item
VBU90201
Description
8-201 BLACK FKM 90D BACK-UP RING
Actual Cross Section
0.139 inch (3.53 mm)
Actual Inside Diameter
0.171 inch (4.34 mm)
Actual Outside Diameter
0.449 inch (11.4 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings