If you do any picture hanging are Hobbies that has to do with finding studs in your wall. You need this if you don't want to keep putting holes in your wall. I am a woman that used to do construction. Ladies if you want to know how to use one the instructions are very easy. There's two types one lights up and 1 beeps when a stud is found. I would not do without it I'm always needing it for some.