Detecto’s Patient Lift Scale weighs a person suspended from a portable patient lift mechanism. It operates on only one (1) 9V battery (not included) with an automatic shut-off feature. The scale also has a membrane keypad with only three (3) keys: ON/ZERO, OFF and LB/KG and features 0.75 in (19 mm) high readouts. It’s so easy to setup and operate; the procedure is quickly learned. The lock-in weight feature stores the last reading when the unit is turned off. 400 and 600 lb (180 and 270 kg) capacities available. Supplied with two spring “O” rings.