Abstract: The invention concerns a lock for doors or windows, with two latches each pivoting about a pivot pin being provided in the one component and of which the mutually facing ends in the locked position engage in mutually opposite directions an undercut surface of a locking bolt mounted on the other component, this locking bolt cross-sectionally being a wedge-shaped or conical tip by means of which the two latches can be forced apart against the opposing force of a spring, this lock being designed so that unauthorized forcible opening in the absence of a key is at least made appreciably more difficult.