The push-button on the base starts the first gear (the faster); second and third gear are automatically selected simply reversing the rotation of the handle.
The drum runs on very wide diameter bearings (s.steel rollers and Delrin balls).
The spring loaded self-tailing disks are self-adjusting.
The base, produced with computer numeric control machines with no cast components, allows easy disassembling and maintenance.
All the gears (made in bronze) run on s.steel roller bearings.
All these models can be powered with horizontal or vertical electric motors and with hydraulic motors.