A turnbuckle for an anti-skid chain that can be mounted on the wheel of a vehicle. A tension cable is connected inside the turnbuckle housing to a winding roll that is pre-stressed in the winding-up direction and mounted so that it can be rotated about its axle. A ratchet wheel with at least one ratchet catch allocated to it is provided on the winding roll and the tension cable can be blocked against its direction of tension by gripping of the ratchet catch into the ratchet wheel. The ratchet catch is moved at least incrementally outwards from the idle position when the wheel isn't moving, in which it is disengaged from the ratchet wheel and the tension cable is not blocked, under the action of the centrifugal force upon rotation of the wheel, and this movement effects a gripping of the ratchet catch into the ratchet wheel.