Abstract: A lock having a freely rotatable barrel, in which there is provided a housing for the lock, a barrel rotatable within the housing, a locking arm and hub rotatable within the housing independently of the barrel, a clutch member on the barrel swingable between engaged and disengaged positions, for engaging the hub member and rotating the locking arm, a clutch control member swingably movable within the barrel, being swingable about the axis of rotation of the barrel, and connecting with the clutch member to move it between its engaged and disengaged positions, and to restrain movement thereof when disengaged, and there being a plurality of generally cylindrical pin members located in the barrel, and lying on axes parallel with but spaced from the central axis of rotation of the barrel, and being movable relative to the barrel and to the clutch control member whereby to secure or release the clutch control member for movement relative to the barrel.