Specifications:

Battery & Charging System Monitor with Dual USB Outlet and One Cigarette Lighter Socket
Accurately monitors battery & charging system voltage
Input: DC12/24V 
Output:  5V2.1A(total）  
2 USB ports
one socket 12/24V
View LEDs and LCD display for your battery's state of charge 
Maximum output current 8A
with CE & ROHS

Packing:

double blister
carton size:55*40*48cm/6pcs/inner box/72pcs/ctn