Review on 🚗 MICTUNING LED Digital Double Voltmeter: Round Panel Voltage Monitor Blue for Cars, Pickups, RVs, Trucks & Dual Battery Packs by Donald Cummings

I used 10 gauge wire and connected it directly to the battery and I didn't notice any voltage drop. What the built in gauge read was exactly what the battery voltage gauge read. According to my tests, it is absolutely accurate. Another plus is that I fitted a cut out cigarette lighter into an unused cigarette lighter and it fitted perfectly so I didn't have to drill a hole for it. (2012 Ram 1500 dealer). I needed a way to control the voltage of my main and auxiliary batteries so they wouldn't get over drained by all the accessories I use when the car isn't running.