the lock housing 14 will cause the double radiused spring 36 to push the bolt 32 back to its single locked position of fig1 referring back to fig2 it becomes apparent that moving the stop 34 from the double lock position illustrated to the single lock position requires moving the stop 34 against the bias of the double radiused spring 36 because the double radiused spring 36 is at an acute angle with respect to the stop 34 moving the stop 34 will increase the resistance of the double radiused spring 36 to this movement until the double radiused spring 36 is pulled into a vertical position continued movement of the stop 34 past this point of maximum resistance the double radiused spring 36 will exit the detent 64 freeing the stop 34 for the remainder of its movement because resistance to movement of the stop 34 from the double lock position occurs over a larger portion of its range of motion than in a conventional locking mechanism and because the point of maximum resistance to this motion occurs after the stop 34 has already moved some distance a locking mechanism of the present invention is more difficult to pick than a conventional handcuff locking mechanism and is also less likely to leave its double locked position as a result of a blow to the locking mechanism while a specific embodiment of the invention has been described in detail.