Abstract: A device for detachable and repeatable accurate clamping in X-, Y- and Z-directions of a first object to a second object like a working table (2) to a machine table (1), the first object (1) having a house (3) with a truncated conical surface (15) intended to cooperate with a corresponding conical surface (25) of the second object (2) and clamping member (9), each intended when clamping the second object to the first object by pivoting the clamping member to engage a clamping surface (20) of the second object by a nose (12). According to the invention the house (3) is provided with a first stop face (17) extending across the axis (16) of the truncated conical surface (15) and cooperating with a second stop face (21) arranged in the second object, the mutual position in the Z-direction of the first and second objects being unambiguously determined.