4 Gang Rocker Dual USB Charger + Digital Volmeter +12V Outlet Pre-Wired Switch Panel Application scenarios: RV, car, yacht, ship, truck, etc. Color: Black; Panel material: water transfer printing aluminum plate; Switch: on / off; Switch LED: blue, red, black (optional); Optional: LED voltmeter (white, green, blue and red); Installation: pre wiring; USB interface: 2 USB (5V 1A / 5V 2.1a)