The Waveshare Liquid Level Sensor with Sensor Modules ROHS is an easy-to-use, cost-effective device that offers precise liquid level detection in a variety of different applications. It consists of two sensing modules with float ball attached at the end of each, allowing it to detect liquid level up to 4m in height. The built-in relays and indicators provide efficient and visual indication of liquid level, and it is also equipped with temperature and humidity sensors for complete environmental monitoring. This product is RoHS compliant and comes with a long service life, making it a reliable liquid level sensing partner.