A clamping device is arranged for releasably holding a tool holder shank and includes a housing, a wedge engagement member reciprocally mounted inside the housing, and a wedge having a first pressure receiving surface and first and second wedge surfaces. An aperture extends radially through a wall of the housing and the wedge engagement member extends radially outwards into the aperture. The first wedge surface acts upon a wedge engagement slide surface on the wedge engagement member and the second wedge surface acts upon an aperture slide surface. The wedge is arranged between a surface of the housing and a surface of a member securely arranged to a drawbar to effectuate a displacement of the drawbar when the wedge is moved inwards, to clamp the tool holder shank. A sleeve is arranged around the peripheral surface of the housing for moving the wedge inwards when the sleeve is moved.