Abstract: A lifter comprising at least a reversible magnet (5, 5') arranged with its polarities oriented along a vertical axis above at least a magnet (6, 6') provided with at least a pair of permanent magnets (6a, 6a') arranged with the polarities oriented along an horizontal axis on the sides of at least a ferromagnetic core (6b, 6b') suitable to contact the load (18) to be lifted, at least a magnetic sensor (11) arranged close to the base (6c, 6c') of said ferromagnetic core, and a further magnetic sensor (12) arranged over said permanent magnets (6a, 6a') so as to measure substantially only the magnetic flux passing through the reversible magnet (5, 5'), as well as a safety device (13) for processing the signals transmitted by said magnetic sensors (11, 12) and obtaining the working point of the lifter on the magnetization curve (14) of the reversible magnet (5, 5').