Specification:Brand new with high qualityInput voltage:DC 4.5 ~ 40V.Output voltage:5V (when the input voltage is between 6.5V ~ 40V).Output current:2A.The voltmeter has automatic calibration function.With reverse connection protection.With overheat protection and short circuit protection.With USB power indicator light.High efficiency and low ripple.Application: can be used on car, electric bike, motorcycle for voltage measurement and to charge phone, iPad, Mp3 etc.Size:approx 5.7 x 2 x 1cm(LxWxH)