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8-208 BLACK FKM 90D BACK-UP RING

Viton® Back-Up Ring, 0.609 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
208
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
5/8 inch
Nominal Outside Diameter
7/8 inch
Unit of Measure
EA
SKU:
VBU90208

Product Specification

-
APG stocks the VBU90208, an AS568-208 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 0.609 in (15.47 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.887 in (22.53 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Expect good resistance to many acids, aggressive chemicals, and petroleum oils and fuels. Viton® (FKM) is widely chosen for long service life in hot, chemically aggressive environments and very low compression set at elevated temperature. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). Exposure to amines or ketones and esters will shorten service life.

Typical settings include chemical processing, oil and gas, and high-temperature process equipment.

VBU90208 ships individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
Item
VBU90208
Description
8-208 BLACK FKM 90D BACK-UP RING
Actual Cross Section
0.139 inch (3.53 mm)
Actual Inside Diameter
0.609 inch (15.47 mm)
Actual Outside Diameter
0.887 inch (22.53 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings