Abstract: A hand tool for tightening or loosening screw elements such as bolts consists of an elbow pipe (24) in which a displaceable and rotatable flexible shaft (26) is mounted. A handle (30) is attached to the rear end of the shaft in order to rotate and displace the shaft inside the elbow pipe (24). A holder (40) with a hexagonal socket for receiving bits is arranged at the front end of the shaft. When the handle is moved to its rearmost position, locking elements cooperate to prevent the holder from rotating in relation to the pipe. When the handle is moved to its forward position these locking elements are disengaged so that the holder and gripping elements can be rotated with the handle.