Genuine Bosch 1612300034 — Stopping device / locking cog. A small, precision-made retention cog used inside Bosch rotary and demolition hammers to lock and locate internal striker/ratchet components so the hammer action works reliably. It’s the exact replacement for the internal “stopping” or locking cog that wears or breaks after heavy use, and is available either singly or as a two-pack for a quick spare on the bench.

Fits (examples): GBH 5‑38 / GBH 5‑40 (and related GBH series), GSH 388, and various Bosch 112xx/113xx rotary-hammer models such as 11240, 11388 and 11264EVS. If your tool’s parts diagram shows a stopping device or “locking cog” with part number 1612300034, this is the genuine Bosch replacement you want.

Notes for the repair: the 1612300034 sits in the hammer/striker area and is replaced during partial disassembly of the housing and gearbox — inspect the mating spring/retainer when you install it and replace any damaged fasteners or clips to ensure correct engagement. The part is made to Bosch tolerances so it restores the original fit and function.

If you need the specific part number to match your exploded view diagram, look for “1612300034” listed as the stopping device / locking cog for your model before installing.

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