GOOLOO(TM) 3.4A 2-Port USB Car Charger LED Display Monitor Car Voltage 180&iexcl;&atilde; Rotation Design Accurate voltage display of the automobile battery, monitor your car's safety anytime.The LOW symbol light on and Beep reminder while car battery voltage below 12v or above 24v Compatible with most digital devices, provide convenience for your every digital product Quickly charge for your two digital devices with intelligent current distribution, and you can make full use of cigarette lighter socket Intelligent IC chipset with under-voltage, over-voltage and short circuit protection 180 degree rotation design, convenient to adjust the perfect angel; Exquisite and mini design, easy to carry and save space