Genuine Fein locking ring (part no. 42616046003) — a spring-steel circlip that secures shafts, bearings and mating components in place when a tool is disassembled for repair. It installs into the machine’s groove to prevent axial movement and restore correct alignment and function. This exact circlip is used on several Fein models — for example MultiMaster/AFMM 18 series machines, Fein RSG EX 18 and RSG EX 1500 B models — and appears on Fein parts diagrams as the replacement circlip for those assemblies.

Sold as the single original Fein part number 42616046003, the ring is the same form, fit and finish you’d expect from Fein replacement parts and is sized to fit the groove shown in the manufacturer’s exploded drawings. It’s best installed with circlip pliers and inspected for wear or deformation before re-use — a simple, low-cost part that returns precise mechanical retention to your tool. (Note: this listing describes the Fein locking ring as specified by Fein’s parts diagrams.)