ACI Corporation in the United States has developed the Stryker electric current meter specifically for measuring surface flow velocity. It is a handheld application type electric current meter and belongs to non-contact flow measurement. Using the principle of Doppler effect, the flow velocity is obtained by changing the frequency of the emitted and received electromagnetic waves. After upgrading and renovation, the functions of flow rate averaging, rainfall shielding, echo intensity indication, angle correction, and timing stopwatch have been added, especially the ability to measure flow in rain without being affected by rainfall. In addition, the Stryker radio current meter can be paired with a Bluetooth module and a tablet computer. The measured flow rate is transmitted to the tablet software via Bluetooth, ensuring reliable data and convenient use.