8-361 BLACK FKM 90D BACK-UP RING

The VBU90361 is an AS568-361 black Viton® (FKM) 90 Shore A Back-Up Ring built to an inside diameter of 5.975 in (151.77 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 6.395 in (162.43 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

This material stands up to petroleum oils and fuels, chlorinated solvents, and aggressive chemicals. That behavior comes from the compound itself: Viton® (FKM) offers the industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C). Verify compatibility before use with low-molecular-weight organic acids or ketones and esters.

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

Stocked as VBU90361 and sold individually. Unit weight is approximately 6.7937 g. As always, verify media compatibility and operating conditions against the requirements of your specific application.