1Hydraulic motor: orbit or piston motor. 2Negative brake: itiscomposed of alternating bronze andsteel disks connectedtothemotorshaftandthebodyofthe winch; pressurized oil from the hydraulic circuit opens the brake andit closed by springs that automatically block the discs when the motor is off. The opening and closing of the brake are determined by the starting and stopping of the motor. 3Planetary reduction gear: It is placed inside the drum and increases the lifting torque, reducing the drum rotation speed with respect to the motor speed. Itis sized to transmit the torque required to lift the maximum load. 4Lowering control valve: it is hydro guided and mounted directly on to the hydraulic motor andit preventstheloadfrom suddenly falling down; that’s why it is considered a fundamental safety device. 5Drum and support structures: the drum is obtained from a steel or casting; the supportstructuresareboltedormadeofweldedsteel making them particularly compact.