Features:1.USB powered devices can be used to measure air , voltage loads , USB terminal equipment working voltage and current  2.The current and voltage cycle , easy to use and practical. 3.Compact and easy to carry , no additional power supply Description:Scope of work: Current (0~2.5A) can detect mobile phone charger voltage compliance DC5V Operating Range : U = 3 ~ 7.5V I = 0 ~ 2.5A Resolution : Voltage 10mV current 1mA Error : voltage <± 1% current <± 2% Full scale drop : ( When measuring current ) 200mV Size:6cm x 2.8cm x 1.5cm Weight:22gThe tester uses a new generation of power four semi~ double loop integral converter IC , with a precision bandgap reference , range accuracy , high precision , stable and reliable performance , strong anti~interference ability , high temperature can be used for measuring USB powered or power consumption of the interface , mobile phone charger , U disk and other products.  Package Included:1 pc x USB charger doctor