This is a JSN-SR04T waterproof ultrasonic rangefinder module, The use of industrial-grade integrated ultrasonic probe design, which is stable performance.Its usage is as same as HC-SR04, the measurement distance is accurate- about 0.5cm, the furthest distance can be measured is 4.5m, because it is small so easy to carry , Suitable for a variety of wet and harsh measurement environments. In general, we will use it in horizontal ranging, obstacle avoidance, automated control, monitoring of objects and its movement, traffic control, security and artificial intelligence, educational research.