Solu 3 in 1 Car Digital Voltmeter Thermometer Automobile Electronic Clock With blue LED// LED digital car clock car digital voltmeter and thermometer automobile electronic clock car 12V supply or cigarette lighter About us (Solu ), Professional factory of circuit boards for Arduino, welcome to our store for more choices with best price. What we pursue is your satisfication of our service, not just for our goods.For any reason you are unsatisfied with our product at any time, simply contact support for exchange or refund. we will reply you about any question you ask within 24 hours Usually, you will get it actually in 9~19 days, If you are in the USA and the item is NOT Fulfilled by Amazon. the item will be sent to you by USPS with shipping information from China. The estimated delivery time offered by Amazon is not the real time. Your patience is highly appreciated. Hope you will receive your item soon and enjoy using it. Function: time, temperature, voltage, three functions in one.working voltage :1.5 ~ 28 v with manual error correction function, temperature setting range -5 ~ 5 Built-in imported long life memory battery, power outages continue to go when the car is turned off.