Differential adjustment wrench for setting and installing the differential of the Citroën 11CV. The tool supports service work on bearings and gears inside the differential housing. The wrench fits a specific ring with an outside diameter of about eighty millimetres. The design allows controlled rotation and positioning during removal and assembly. The adjustment wrench helps set clearance and preload according to the technical requirements of the vehicle. Suitable for use in a workshop environment with hand tools. Intended for technicians working on the rear axle of this model.