A pin tumbler cylinder lock that is virtually pick proof comprises a cylinder housing having a single bore and a cylinder key plug arranged in the single bore. The pin tumbler cylinder lock also comprises a cavity having a predetermined shape in a predetermined portion of the housing. The pin tumbler cylinder lock also includes a lockout sleeve arranged over the cylinder key plug wherein the lockout sleeve may rotate within the cavity to create a lockout mode for the pin tumbler cylinder lock when a lock picking attempt is occurring thereon.

A pin tumbler cylinder lock that is virtually pick proof comprises a cylinder housing having a single bore and a cylinder key plug arranged in the single bore. The pin tumbler cylinder lock also comprises a cavity having a predetermined shape in a predetermined portion of the housing. The pin tumbler cylinder lock also includes a lockout sleeve arranged over the cylinder key plug wherein the lockout sleeve may rotate within the cavity to create a lockout mode for the pin tumbler cylinder lock when a lock picking attempt is occurring thereon.

A lock and key combination providing extra code combinations. The lock has a housing and a cylindrical key plug with a keyway and at least side locking tumbler. The side locking tumbler has, at its rear side, a tongue which will fit into an associated recess in a side bar. The outer surface of the tongue is shaped as a groove between two vertical edge portions. One of these edge portions will make contact with the sidebar, adjacent to an entrance opening of the recess in the sidebar and thereby stop the tongue from entering into the rectangular recess if the side locking tumbler is rotationally misaligned. Because of this, it is possible to design the cylinder lock with a large number of predetermined code positions for each side locking tumbler. An associated key with a key blade having a wave-like side code pattern, will have, for each side locking tumbler, a selected one of a large number of predetermined different code positions.

A pick-resistant lock assembly may include a housing having a cylindrical opening. The cylindrical opening may have a centerline. The housing may include a plurality of pin cavities intersecting the cylindrical opening. A plug may be rotatably mounted in the cylindrical opening. The plug may include a keyway and a plug axis. A slide bar pocket may be formed within the housing. The lock assembly may include a pin verification mechanism having a slide bar in the slide bar pocket. The pin verification mechanism may be concealed within the housing and may be inaccessible to an attacker inserting a hand tool through the keyway. Other examples may be described and claimed.