A driver for medical wires has a hollow drive shaft, rotatable about a rotation axis. The hollow drive shaft has a distal end and a proximal end. Furthermore, a plurality of clamping jaws penetrates under an angle into the hollow drive shaft close to its distal end. The clamping jaws are moved into or out of the hollow drive shaft by means of a jaw guide mounted slidable parallel to the rotation axis and movably connected to the clamping jaws. An actuator is provided to shift the jaw guide parallel to the rotation axis and therefore modify the penetration depth of the clamping jaws.