cevans, i used to use my open water finder on the ice with my law tractor batt. i made a t-bar and attached the transducer to it. worked just fine like that but i used 2 holes, so not to snag up on it. actually a shallow hole, full of water, next to the fishing hole, would work just as good. i did have an eagle unit csreen freeze up on me at -10 one day. it went black and when it warmed up, it had lines in the screen the rest of its life.