The invention relates to a lock-key system, including a key that is insertable into a key channel of a lock cylinder, and traceable by core pins or by locking elements that are displaceable in the cylinder core, wherein in case of a match, the cylinder core can be rotated by means of the inserted key. Lettering in the form of an impression and/or an embossment, serving as an identifier and including letters and/or numbers and/or symbols, is introduced into at least one lateral surface of the key shank and in case of a lateral profiling, into the lateral profiling. The lettering or individual letters, numbers, or the symbol or sub-areas thereof are traceable by core pins or locking elements having a correspondingly formed contact surface.

A sash window fastener includes: a latch assembly; a sash lock assembly mounted upon the meeting rail; and a stop member mounted to the master window frame. The lock assembly includes a pivotable cam to engage a keeper on the master frame to lock the window, and a pivotable follower arm. The arm interconnects with the latch assembly within the meeting rail, so cam rotation that drives arm rotation also causes translation of the latch. The cam may occupy: an extended position to secure the cam to the keeper, with the latch engaging the master frame to prevent tilting, and being positioned below a protrusion on the stop member to redundantly lock the window; a first retracted cam position permitting sliding of the window; and a second retracted position permitting tilting of the sash window. Additional protrusions may be used on the stop member to serve as vent stop positions.

A dual-ring tubular lock assembly is provided. Inner and outer walls of a key are formed with inner-ring and outer-ring notches. A lock cylinder is inserted in a central through hole of a lock housing. A front end of the lock cylinder is formed with a tubular keyhole. The tubular keyhole is formed with inner-ring and outer-ring grooves corresponding to the inner-ring and outer-ring notches and mounted with inner-ring and outer-ring key pins. A rear end of the lock cylinder passes through a central perforation of a lower bead seat and extends out of the lock housing. The lower bead seat is fixed in the center through hole. The lower bead seat is formed with inner-ring and outer-ring holes corresponding to the inner-ring and outer-ring grooves and mounted with inner-ring and outer-ring driver pins and springs. The latch is fixed to the rear end of the lock cylinder.

A tubular lock and its operating key have safety features that render the lock and key well suited for use with food freezer appliances and the like where the keyway of the lock extends horizontally. The tubular portion of the operating key, and the keyway of the tubular lock are cooperatively configured so a key inserted into the keyway of the lock fits quite loosely and is minimally supported even when fully inserted. The graspable bow of the operating key is made unusually long causing the center of gravity of an inserted operating key to be spaced far from the front face of the lockso the weight of the loosely fitting and minimally supported operating key levers the graspable bow downwardly, causing the key to drop from the keyway unless being held in the keyway. Gravity is optimally used to effect key ejection.

A key and a lock cylinder, which are formed such that the guiding the key into the keyhole and the key canal occurs precisely and in a user-friendly manner. The precise placement of the key in relation to the lock cylinder and its parts enables even distribution of the forces directed onto the key and the lock cylinder.