Yes. It doesn't work through air, air pockets, milky ice, large air gaps (i.e. you have to get down on your hands and knees and touch the ice with the "flashlight" looking device, and wet the ice perhaps--spit, pee, or dump some water on it).
![Wink ;)](https://www.iceshanty.com/ice_fishing/Smileys/default/wink.gif)
Check out the Marcum unit LX1. More Power! Funky battery. Lasts a long time though.