The Virtual Make “Water Velocity Logger” Model: DVI-K20 is a small electronic hand-held device that can be used to measure flow velocity from mechanically rotating current meter. A superior feature of the DVI-K20 is its ability to store up-to five current meters data at a time and interface directly to a Laptop, Pocket-PC, or other computing device and provide data in MS-Excel File Format that can be used externally to compute discharge.