Variable width mower for grass, mounted type in agricultural vineyards and gardens, used on tractors with power from 30 to 120 horsepower. The hydraulically adjustable variable working width is equipped with two maximum anti-shock valves, which allows you to work safely in rows of any width. The transmission is mechanical, consisting of three gears that transmit motion to the articulated type knives through high-resistance trapezoidal belts and guarantee a perfect cut thanks to the maximum crossing and counter-rotation of the rotors. In organic cultivation, it is possible to combine the machine with two hydraulic mowers on the inter-row rotors to avoid damaging the plant itself while passing.