A hook formed into a body having a hook shape and having a neck and fabricated from nonferromagnetic material with the body having a first end and a second end. Said control unit has rigid plastic housing encloses a printed circuit board, a battery, a ball-rolling switch, and an integrated circuit processor. The SoS nets are the logical complement of preferably all the exempt areas of an IC floorplan. The inlet valve has a pretensioning element, a closing element, and a sealing seat, which sealing seat is built on the plate element. The depth to which the surface treatment elements are impinged is precisely controlled to achieve the desired magnitude and depth of compressive residual stress.