Designed to be used in various fields; has the following features. * Compact and lightweight (lighter than a hand-operated chain block) *Speed control: Operator can control the chain speed freely as he likes by a pilot control system. *Automatic lubrication by a built-in lubricator keeps the hoist free from motor troubles. *Safe: No mechanical brake. Self-locking worm gear provides automatic and positive braking. Holds loads securely when the motor is not operating. No motor burn-out, can be overloaded, even repeatedly stalled, without damage to any parts of the chain block. Over-load will only stop the operation of the air motor. *No shock hazard: Controlled and powered completely by air. *Explosion-proof type *Required air pressure is 0.59 MPa (6 kgf/cm2).