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8-104 BLACK FKM 90D BACK-UP RING

Viton® Back-Up Ring, 0.112 in ID x 0.103 CS, 90A, Black, -15 to 400°F

Status
Out of Stock
Est. Ship Date
20 Oct 2026
Material
Fluoroelastomer (FKM/Viton)
Dash Size
104
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
3/32 inch
Nominal Inside Diameter
1/8 inch
Nominal Outside Diameter
5/16 inch
Unit of Measure
EA
SKU:
VBU90104

Product Specification

-
Ordered as VBU90104, this is an AS568-104 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 0.112 in (2.84 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 0.318 in (8.08 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

As a material, Viton® (FKM) is widely chosen for very low compression set at elevated temperature and outstanding high-temperature capability. The material holds up against many acids, chlorinated solvents, and engine and transmission fluids. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Exposure to ketones and esters or low-molecular-weight organic acids will shorten service life.

Maintenance and OEM teams specify it across oil and gas, semiconductor equipment, and automotive fuel systems.

Reference part number VBU90104 when ordering; the item is sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Item
VBU90104
Description
8-104 BLACK FKM 90D BACK-UP RING
Actual Cross Section
0.103 inch (2.62 mm)
Actual Inside Diameter
0.112 inch (2.84 mm)
Actual Outside Diameter
0.318 inch (8.08 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings