1.3 In 1 Voltmeter: Combines a digital voltmeter, thermometer, and car charger in one sleek device for 12V/24V vehicles. Realtime monitoring of battery voltage and interior temperature via LED display provides immediate insight into vehicle electrical health while you travel. 2. Car Cigarette Lighter: Inserts directly into the cigarette lighter socket without tools or professional skills required. Provides continuous power to your devices through a stable 5V USB output while simultaneously displaying accurate readings on the digital display. 3. Voltmeter: Monitors battery voltage from 0 to 30V and temperature from 9 to 80 degrees Celsius. precision sensors use chemicalresistant electronic components and an ABS housing for lasting performance under varying driving conditions. 4. Digital Display: Bright dualcolor LED screen clearly shows both voltage and temperature at a glance. Easy readability day or night with a low power consumption design that does not drain your vehicle's battery. Use scenarios daily commuting and long road trips: monitor battery health and cabin temperature in real time to prevent unexpected electrical issues and maintain comfort. cold or extreme weather: keep an eye on battery voltage while ensuring interior temperature stays within a comfortable range, helping you plan for charging or warming up the vehicle. fleet or multivehicle use: quickly assess battery status across 12V/24V vehicles with a single, compact device that provides stable USB power and realtime readings.