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-421 BROWN FKM 90D O-RING

Viton® O-Ring, 3.975 in ID x 0.275 CS, 90A, Brown, -15 to 400°F

Status
Out of Stock
Est. Ship Date
20 Oct 2026
Material
Fluoroelastomer (FKM/Viton)
Dash Size
421
Durometer
90 Shore A
Cross Section Type
Round
Color
Brown
Minimum Temperature
-15°F (-26°C)
Maximum Temperature
400°F (204°C)
Nominal Cross Section
1/4 inch
Nominal Inside Diameter
4 inch
Nominal Outside Diameter
4 1/2 inch
Unit of Measure
EA
SKU:
VB90421

Product Specification

-
This o-ring is supplied in AS568-421 brown Viton® (FKM) 90 Shore A measuring an inside diameter of 3.975 in (100.97 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 4.525 in (114.94 mm), catalogued under part number VB90421. It remains the most cost-effective sealing element available for pressurized assemblies.

Viton® (FKM) is specified here for very low compression set at elevated temperature and industry benchmark where nitrile reaches its thermal limit. This material stands up to aggressive chemicals, engine and transmission fluids, and petroleum oils and fuels. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in amines or hot water and steam.

Typical settings include automotive fuel systems, aerospace, and semiconductor equipment.

Stocked as VB90421 and 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
VB90421
Description
-421 BROWN FKM 90D O-RING
Actual Cross Section
0.275 inch (6.99 mm)
Actual Inside Diameter
3.975 inch (100.97 mm)
Actual Outside Diameter
4.525 inch (114.94 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6005
Product Category
O-Rings - Bulk - Commodity