3 in 1 Cigarette Socket Panel - This 12v socket panel is designed with 12v RV usb socket + LED digital display voltmeter + 12v cigarette lighter socket. Three-hole multi-functional panel for DIY work , detachable to replace other charger plugs or any other equipment of your choice. Convenient to install and use. Cigarette Lighter Adapter Splitter - Extension of the cigarette lighter socket, sufficient for simultaneous use of a variety of portable devices in your vehicle. Waterproof Dual USB Charging Socket - This 12v USB car socket has two built-in USB charging ports, two-port output: 5V / 1A and 2.1A (total 3.1A), automatically detect your devices and charge simultaneously 2 devices at optimal speed! Real-time LED Voltmeter: With a large digital voltmeter screen displaying 5-48V voltage, you can monitor the battery condition of your car or boat if the voltage is under normal state. Overload protection - overheating, overcurrent, overload protection; This dual USB charger socket is