We choose this inexpensive and simple multimeter because it has just the functions you need without the needing a doctorate in electrical engineering in order to use it. When working with a bundle of wires (mast light wiring comes to mind) it's great for identifying positive vs. negative wires and the function of individual wires. Use for testing the boat battery, electrical devices, switches, breakers, as well as electrical continuity to identify a short or burned out bulb.

Search far and wide on the internet and you may find it for a few bucks cheaper elsewhere depending on the day. We have them here for your convenience so you don't have to try to decide which one you should choose from the hundreds available on the internet.