JSN SR-04T Waterproof Ultrasonic Sensor
JSN-SR0T4 is basically a waterproof ultrasonic distance measurement sensor module that can give 25cm-450cm non-contact distance measurements, with a ranging accuracy of near about to 2mm.
JSN SR-04T sensor module having an industrial-grade integrated ultrasonic sensing probe design, waterproof type, stable performance as well as high precision. It can be also be utilized in horizontal ranging, obstacle avoidance, automated control, analyzing of objects as well as their movement, traffic control, security and other applications.
It utilizes the same transducer to both transmit as well as receive the signal so it requires time to switch from one mode to another.
The sensor itself is enclosed in a waterproof enclosure, which might be helpful if you want to place it outside in harsher environments.