8-118 BLACK FKM 90D BACK-UP RING

APG stocks the VBU90118, an AS568-118 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 0.862 in (21.89 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.068 in (27.13 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

This material stands up to petroleum oils and fuels, chlorinated solvents, and engine and transmission fluids. Viton® (FKM) delivers long service life in hot, chemically aggressive environments and outstanding high-temperature capability. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. It is not the right choice where ketones and esters or low-molecular-weight organic acids are present.

Maintenance and OEM teams specify it across automotive fuel systems, chemical processing, and aerospace.

VBU90118 ships individually. Unit weight is approximately 0.3678 g. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.