AEM-USB small electromagnetic current meter, equipped with a two-dimensional electromagnetic current sensor, temperature sensor, and compass. The temperature sensor is a standard sensor, while the flow rate sensor can measure flow rate and direction. The AEM-USB has a compact appearance and is easy to carry, making it suitable for various occasions such as oceans, lakes, ponds, and rivers. The equipped software is used to display measured data (flow rate, direction, water temperature, etc.) on the computer, and the software also provides data averaging calculation function.