This is a simple water sensor ,can be used to detect soil moisture .Module Output is high level when the soil moisture deficit,or output is low.Can be used in module plant waterer device, and the plants in your garden no need people to manage * Operating voltage:3.3V~5V * Dual output mode,analog output more accurate * With power indicator (red) and digital switching output indicator (green) * Having LM393 comparator chip, stable