The power transmission in the SDS-Quick System works via a form-fit, in the conventional cylinder shaft system via a friction locking. While the connection between the drill & the jaw in the cylinder-shaft system is based on friction, the power transmission between the shaft & the drill chuck is ensured form-locking in the SDS-Quick System. This means less friction losses & hence an optimum transmission of the torque. The Quick-Change system permits one to change the drill in a few seconds without any tool. SDS-Quick drill can also be used in the conventional three-jaw drill chucks (with or without key).