The power transmission functions across a positive form lock in the SDS-Quick System & across a friction grip in conventional straight shaft system. While the connection between drill & jaw is friction based in the straight shaft system, the power transmission between the shank & drill chuck is ensured by interlocking in SDS-Quick System. This signifies lesser frictional losses & thereby an optimum transmission of torque. The Quick-Change System permits changing the drill in seconds without using any tools. SDS-Quick Drill can also be used in conventional three-jaw drill chucks (with or without key).