Abstract: The invention is a unibody key with lateral grooves on one side or both sides of the shank of the key. The lateral grooves are of an irregular pattern and are cut at a depth such that the key can be snapped off along the lateral groove. The snapped-off portion ofthe key can be inserted in a lock. By inserting the snapped-off portion in the lock, only a key which will mate with the irregular pattern of the snapped-off portion will give proper alignment for a key to open such lock. By such operation, the key necessary to open the lock is easily, quickly and effectively changed.

Abstract: A programmed steering and cutting blade control apparatus for self-contained lawn mowers with a nylon tape having rectangular members disposed on the upper and lower surfaces of the nylon tape which extends between two reels where the rectangular members actuate micro switches disposed below the nylon tape and actuate micro switches disposed above the nylon tape where such upper micro switches are connected to a plate which is reversible so as in one instance to reverse the plate and the micro switches are disposed away from the nylon tape and not actuated. Two lower micro switches actuate a turning wheel motor and a third micro switch actuates a brake. The upper micro switch actuates the cutting blades. The movement of the programmed nylon tape is synchronized with the movement of the drive wheels to ensure the self-contained lawn mower moves along the preplanned route.