8-269 BLACK FKM 90D BACK-UP RING

Part number VBU90269 is an AS568-269 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 8.734 in (221.84 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 9.012 in (228.9 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

It resists petroleum oils and fuels, aggressive chemicals, and chlorinated solvents. That behavior comes from the compound itself: Viton® (FKM) delivers excellent resistance to compression set and permeation, outstanding high-temperature capability. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C).

Maintenance and OEM teams specify it across high-temperature process equipment, chemical processing, and automotive fuel systems.

Reference part number VBU90269 when ordering; the item is sold individually. Nominal inside diameter is listed as 8 3/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.