Abstract: A tool holder attachable to a spindle of a hammer and which can receive a bit, the bit having a shank with at least one retaining groove extending along part of the shank, the retaining groove having a defined length, a front end and a rear end that limit axial movement of the bit in the tool holder, which tool holder comprises a hollow cylinder having an axis, an axial bore, a rear end that can be attached to the spindle of the hammer, and a front end that can receive the shank of the bit so that the bit is slidable within the cylinder in an axial direction, at least one retaining element that is located so that it can extend radially into the bore of the cylinder and into the at least one retaining groove of the bit so that the retaining element can be hit by the rear end of the retaining groove during the transition to idling and limit the extent of axial movement of the bit within the cylinder, at least one radial restraining element limiting movement of the retaining element in the radial direction, at l

Abstract: A rotary hammer is provided which comprises a tool holder (2) and an air cushion hammering mechanism which comprises a cylinder (8′) having one end (8) that is connected to the tool holder, a piston (9), a ram (10) and a beat piece (21) slidably located in the cylinder so that reciprocation of the piston in the cylinder will cause the ram to reciprocate in the cylinder and thus cause the beat piece to hit a bit located in the tool holder. The ram (10) has an annular recess (31) in its peripheral surface at the end thereof nearest the piston (9), in which recess is located an annular seal (30). The annular seal has an annular seating flap (36) lying on the radially outwardly directed surface of the recess and an annular sealing flap (38) that is joined to the seating flap and extends between the radially outwardly directed surface of the recess and the inner wall of the cylinder (8′).