ANVER'S M250M mechanical lifter requires no external power because it has a self-cycling valve and piston that creates a powerful vacuum when lowered from a crane onto a load until the chain slackens fully and is raised again. Featuring a new 21 x 29-in. sealing ring suction pad which can be replaced in the field using a common Allen wrench, this energy-saving vacuum lifter has a 2,800 lbs. capacity for feeding cutting tables and machining centers. The large rectangular suction pads lift heavy blocks of aluminum or steel.