The water drains vertically from a transparent supply tank through a nozzle due to the hydrostatic pressure. The velocity of the jet can be measured with a Pitot tube and a U-tube manometer. The jet diameter is measured with a micrometer. 5 easy to interchange nozzles are included. The water level can be set precisely using an overflow. The water supply is provided either from the laboratory mains or using the Hydraulic Bench.