I bought this Hummingbird fishing buddy a little over a year ago. It was on sale for $110 at the time. It works great for me, shows water temperature also. It does take 8 AAA batteries though. I get on average about 14 hours of continuous use. I just don't leave it on continuously while fishing, that way I get several fishing trips on one set of batteries.
https://www.amazon.com/Humminbird-41.../dp/B013T5QS30