This measuring device is extremely compact and serves for semi-trailers and solo vehicles. Because the Foreign Ministry is certified, it can be used for its own purposes as well as for the commercial operation of the measurement. It serves to measure the flow of all oil derivatives, with a flow rate of 130-1300 l / min. Depending on the performance of the vehicle, unloading of multiple chambers is possible simultaneously. This system does not require gas separator, volume and very unnecessary moving elements. Therefore, the installation, maintenance and daily work is drastically facilitated, and also the depreciation is reduced to a minimum.