DIY Design - Any port of this charger socket panel can be exchanged place with other ports and also can be replace with additional USB outlets, or anything else that fits. Do it by yourself, whatever you like. Wide Compatibility -This 4 in 1 charger socket panel is widely used for 6-30V car, truck, Motorcycle, RV, ATV, boat, Camper Vehicles, etc. The USB socket port fits for charging iPad, iPhone, iPod, HTC, Galaxy, Blackberry, MP3 Players, Digital Cameras, PDAs, and Mobile Phones. LED digital display looks cool, especially in dark. Over-charge Protection - Display the current detected by the intelligent circuitry while charging. Intelligent circuit design protects against excessive current, overheating, and overcharging. Ensure the charging safety. Safety Driving- The LED voltmeter shows 6-30V voltage when driving which can remind you whether the voltage is at a normal level, ensure driving safety. Color: Blue/Green/Red 4 in 1 Multi Function Panel, 2 USB Socket Charger 2.1A & 2.1A +LED Voltmeter + 12V Power Outlet + ON-OFF Toggle Switch, Four Functions panel for Car Boat Marine RV Truck Camper Vehicles Specification : Material: ABS Weight: 131g (4.6 ounce) USB socket output: DC 5V / 4.2A Power outlet: DC 12V Voltmeter display range: 6 - 30V. Voltmeter socket dimension: Approx. 28 * 16mm (Screw Diameter * Height) Power socket dimension: Approx. 29 * 40mm (Screw Diameter * Height) ON-OFF Toggle Switch: Approx. 29 * 18mm (Screw Diameter * Height) USB socket dimension: Approx. 29 * 40mm (Screw Diameter * Height) Four hole panel dimension: Approx. 104 * 87 * 5mm (L * W * H) Package Include: 1 x Digital Voltmeter 1 x 12V Cigarette Socket 1 x Double USB Power Socket 1 x ON-OFF Toggle Switch 1 x Four Holes Panel 4 x Stainless Steel Screw 9 x Blue Terminal