Review on Lucky Portable Sonar Fish Finder: Waterproof Handheld Wireless Fishing Finder for Boats, Kayaks, Ice Fishing, and Sea Depths by Steven Loy

I was looking for something portable, inexpensive and simple that would allow me to measure depth and temperature in different areas of the large lake I live on. I also have closed loop geothermal heating for my house which was installed 15 years ago. Questions are currently being asked about the gradient of the lake and whether it affects the geothermal system. It's that simple: just go out with a fishing rod and a depth finder and map the bottom of the lake. Also, our grandkids seem to want to swim in unfamiliar places and it's so easy, just cast out a line and measure the depth. Yes I have a depth gauge on my boat but it is not easy to maneuver our pontoon in some places to use it.