This 3 n 1 soil tester is a really nice one. This one checks the moister of the soil, the lighting for the plant as well as the pH/acidity level. There is no batteries needed to make to make it work. You can use it for your indoor plants as well as your outdoor plants and in your garden to make sure your veggies are getting everything that they need. This is a pretty awsome little device and the price is great as well too.