SMAKN&reg; Mini Discharge USB Load Resistor Current Tester 0.4a-2.1a Adjustable Constant Current USB Electronic Load with FAN Working voltage: DC 3.6V-6V Discharge current: 0.4A-2.1A continuous adjustable (the actual range slightly larger) Current work error: no more than 3% + 5mA Under continuous discharge power: 7.5 W (no fan) (under 5V 1.5 A current, more than the power is not easy to work long hours)