JEBSENS - 3.4A 17W Dual USB Car Charger, Cigarette Lighter Voltmeter with LED display Digital Panel Meter Voltage Monitor for Auto Car Truck, Blue LED Display with Smart Low Battery Alarm - Black LED DISPLAY SHOW VOLTAGE: Dual Charger With Blue LED screen, The voltage indicates the health of your battery and allows you to know when it's time for a replacement. SMART VOLTAGE ALARM: When the voltage is below 12v or above 24v, the red light will light up (This new model is without the annoying "beeps" sound). RED LIGHT LIGHTS if the voltage falls or rises out of the optimum range. This can be a huge advantage over other models as you do NOT want to find yourself stranded out in the boondocks in the middle of that dry heat with not enough power in your battery to get back home. INTELLIGENT QUICK CHARGE: The Dual USB Charging Port Pump out 17W of power, With Intelligent Chip inside, The current will automatically share while using. Charge any of your devices quickly and safely with Overcharge / Overheat Protection. ADJUSTABLE CHARGING PORT & VOLT DISPLAY: The USB Port and LED Volt Display are flexible and can be rotated 180 degree, provides you the best viewing angle Package Includes: 1*3.4A Voltmeter Car Charger, 1*User Manual. 1 Year Warranty provided. Order Now and Enjoy 100% Satisfaction Guarantee from Jebsens.