Features:
It can be used as battery voltage monitoring， for 12V cars， SUV， 24V trucks， buses.
It can be a USB charger， for the charger of 0-2.1A cell phones， like for iPhone / Samsung， digital cameras， tablet， etc.
Its compact size is easy to use.
Display of high brightness is for easy viewing.
 
Specifications:
Power mode: Cigarette lighter style
Voltage measuring range: DC 8-40V ( DC 12V/24V Universal )
Display: 3-bits， Red LED digital tube
Voltage error: 0.1-0.2V
USB output voltage: DC 5.0-5.1V
USB output current: 0-2.1A
Applicable type: For iPhone / iPad / iPod & Samsung and other devices
Size: 75mm * 40mm / 2.95 * 1.57in
Package size: Approx. 13 * 8 * 4cm / 5.1 * 3.1 * 1.6in
Package weight: 40g / 0.89lb

Package List:
1 * 2in1 Digital Voltmeter and USB Charger