Exactly what I was looking for. No more days of dead batteries while out fishing.

I have used these in the past for use with my trolling motors. However, this year I realized how handy they are for use with my travel trailer. As a result, I bought another for me and some for family and friends who have trailers. The device not only lists the voltage but it gives an idea of the amount of charge left. This is very helpful when you are trolling but it is also helpful so that I know how much time I have before my trailer battery needs to be charged. It isn't fun to run out of juice in the middle of a cold night and not have the furnace work in the trailer.

It's easy to use and simple, the downfall is that I expected something that could be attached to the battery and keep a constant reading of the power remaining. However I'm very pleased for what I paid.