Abstract: The combination can be set by discs which are toothed on one of their faces. This toothing causes movement of internal bushes or rings which are at least partly contained in seats in a manually controllable slider, which can be moved against a spring when, having set the exact combination, a radial passage in said bushes or rings becomes disposed in a position such as to allow radial movement of the bushes and thus movement of the slider and opening of the lock. The combination can be changed by setting the existing combination and moving the slider and thus the rings, so that these latter disengage from the toothed discs which can thus be rotated into another position without dragging the bushes with them.