Don ' for t bother to look at the numbers on various indicators, when they call, and make your life easier The standard size button battery can last for year At the same for time, there is a light sensor at the bottom of the product, which will stop working at night to avoid disturbing your rest There are 4 fours, black / blue / red / yellow, selecting your favourite color Most potted plant deaths are caused by water shortage or excessive watering This lovely soil humidity sensor will when the soil is short of water to remind you to water the So you don ' for t have to water much for fear of water shortage It ' s very simple to use Just pull out the sheet at the bottom and it will start to work When you just insert it into the soil, it will make the calls of birds or frogs, but once is detected in the soil, it will stop singing, Manufacturer: YanFengPro