A paper processing tool includes a base having a receiving area for selectively receiving a sheet of paper. Various controls such as auto-cruise control and so on as well as the turn onoff of the stop lamp can be simultaneously performed by the one magnet mounted on the operating body of the switch for vehicles. The alerting pod can be either screwing meshed into the recess socket for normal measuring and alerting function or screwing detached off the recess socket for battery recharging operation. A controller is operatively connected to the modules, and is operative for preventing reading interference between the modules during reading. For improving the repeated precision of the positioning of one of the coupling parts relative to the other coupling part even upon high stress on one of the coupling parts in circumferential direction a clamping plate is provided between the lateral surface and the associated flank which is axially elastic and is mounted to one of the coupling parts.