The cutting unit consists of three main parts: the hydraulic motor, the aspirator and the cutting blade. The air is aspirated in the opening through the grid. A few mm from the grid there is a cuttling blade which with its rotation cuts the leaves aspired through the grid. The cutting blade is connected to the axis of the aspirator so it rotates at its speed. The leaves cut are discharged by the air jet and pushed downwards to the ground.

Besides having a protective function against possible intrusions, the grid aligns the leaves towards the cutting bar and operates as a barrier for the grapes.

The two conveying plates at the sides of the cutting unit, convey delicately the stalks towards the grid allowing to remove the leaves with the least possible damage. The two aspirators - defoliators can be mechanically adjusted by means of a bolt (fulcrum) and then make the operation area larger according to the needs ( min 400 - max 800).

Very good results are obtained moving the tractor at a speed of about 4- 7 km/hour. The approaching movement of the defoliator to the leaves is made by the operator simply approaching or moving away the cutting unit by means of a hydraulic control. The defoliator pushes the stalks and the grapes to the side and allows the strong air flow to pull the leaves inside the grid where they are smashed and cut by the rotating blades.