Review on 🔌 DaierTek 2pcs 12V Dual USB Charger Socket for Car Marine RV RZR Boat ATV Bus Truck, Quick Charge 3.0 Waterproof with LED Voltmeter and Wire Fuse Kit - Enhancing Automotive Searchability by Anthony Boylan

So far so good, replacing one of my standard outlets wasn't a problem. They cut off corners on the wire they send along. It's aluminum wire, not copper, it will work, but you really need to save some money. If you don't put this on the switch, it will always show your battery voltage. It is possible that this could destroy your battery if you have an old battery or if you leave the car idling for a long time. I've left my truck for 2 days with no problems but the voltage has dropped from 12.5 to 12.3 so it's either it or not. If you're really concerned, plug it into a switched cable or set a switch for it. I personally like the battery voltage readings. My phone seems to charge as expected.