Abstract: A key blank including a generally elongate shaft portion defining a key combination surface adapted to have formed thereon key cuts which define a key combination, the key blank including a movable pin element retained within the elongate shaft portion, the movable pin element being displaceable in a single direction, outwardly from the key combination surface.

Abstract: A key blank including a generally elongate shaft portion defining a key combination surface adapted to have formed thereon key cuts which define a key combination, the key blank including a movable pin element retained within the elongate shaft portion, the movable pin element being displaceable in a single direction, outwardly from the key combination surface.

Abstract: A key blank including a generally elongate shaft portion defining a key combination surface adapted to have formed thereon key cuts which define a key combination, the key blank including a movable pin element retained within the elongate shaft portion, the movable pin element being displaceable in a single direction, outwardly from the key combination surface.

Abstract: A vehicle anti-theft device comprising a gear shift lock and an ancillary vehicle anti-theft device which is operated automatically by operation of the gear shift lock.

Abstract: A cylinder guard including a plurality of guard plates, at least one of which is formed with a plurality of non-rotatable bolt head seats and a plurality of bolts having heads non-rotatably seated in the non-rotatable bolt head seats and arranged for mounting the cylinder guard onto a door.

Abstract: A cylinder lock including a housing and a plug disposed in the housing and arranged for rotation relative thereto, a first plurality of chambers formed in the housing and a second plurality of chambers formed in the plug and arranged such that each one of the first plurality of chambers extends coaxially with a corresponding one of the second plurality of chambers, when the plug is in a first rotational orientation relative to the housing, a first multi-element pin assembly being disposed in said first plurality of chambers and a second multi-element pin assembly being disposed in said second plurality of chambers, the first multi-element pin assembly including an outer pin element having an axial recess and an inner pin element disposed for selectable axial orientation relative to the outer pin element and apparatus for retaining the inner pin element against disengagement from and undesired misalignment with respect to the outer pin element.

Abstract: A pin tumbler lock comprises a cylindrical shell, a plug fitted within the shell, and rotatable by key means. The plug has first bores for receiving first pin tumblers. The first bores are substantially normal to the axis of the plug. The shell has second bores for receiving second pin tumblers therein. The second bores are aligned with first bore. First and second pin tumblers are located in bores. The second pin tumblers are forced by a spring into the aligned first bores to thereby prevent rotation of the plug. The first and second pin tumblers have substantially mating surfaces at respective ends providing contact along their entire length. The plug includes two grooves in a plane normal to the axis of the plug along its periphery, one groove on each side adjacent to first bores, thereby providing a non-linear shear line between the plug and the shell.