Original Bosch trigger / on‑off switch, part no. 1617200559 — a stepless (variable‑speed) trigger switch designed to restore reliable on/off control and speed modulation to compatible Bosch rotary hammers.

Direct replacement for a range of GBH series tools (commonly fitted to GBH 2‑26 / GBH 2‑26 F and several GBH 2‑22 / GBH 2600 / GBH 2400 variants), matching the original connector and mounting footprint so it installs into the handle without housing modifications.

Listed as part number 1617200559  and included on Bosch power tool parts lists for certain 110–127 V GBH model variants — a genuine Bosch component intended to preserve the tool’s original performance.

Compact, plug‑in design built to the same specifications as the factory unit; if your hammer’s symptoms are intermittent power, no start, or loss of variable speed control, this original Bosch switch is the correct service part to return the tool to working order. This switch is listed among Bosch power tool parts for multiple GBH 2‑series rotary hammers.

Browse our full range of Bosch hammer drill parts.