The flow measurement in open channels is widely used and applied in the environmental and geotechnical fields. The V-notch flow meter causes a variation of the water level of the tub where it has been installed directly proportional to the flow rate variation. V-notch flow meters transform the value of the water level in a measurement of instantaneous flow rate of the channel to which it is applied. The level measurement is done by an electric transducer. Gestecno provides V-notch flow meters in thin-wall steel of different shapes (triangular, trapezoidal, etc.) according to the extent of the flow rate that has to be measured.