Sansys 2 in 1 Cigarette Lighter Digital Red LED Voltage Monitor 12 V 24V+ Dual Port USB Car Charger 5V/3A For iPhone/iPad/iPod SPCARSETS01 (Car charger with battery Voltage) 2-in-1 function: car battery voltage monitoring,for 12V cars, SUV, 24V trucks, buses; USB charger, for charging cell phones, digital cameras, tablet pc and etc. Dual Port 3.1A USB Car Charger charges your favorite mobile devices including the iPad, iPhone, iPod, HTC, Galaxy, Blackberry, MP3 Players, Digital Cameras, PDAs, Mobile Phones. With battery voltage monitor,Constantly monitor battery voltage, extend and protect the battery come with bonus: 4 piece Tire Pressure Indicator Valve Stem Caps kit , when the tire pressure is low to help avoid premature tire wear or blowouts from under-inflated tires Power mode: cigarette lighter style; USB Output: DC 5.0-5.1V; 0-2.1A, Voltage measuring range: DC12V/24V Stylish, Compact design(1.18*1.18*2.44 inchs 0.02g ), Easy to use, easy to carry. yet able to keep charging your devices anywhere and anytime!