... no cold solder ,lack of components, no tin dross, no short-circuit, no open circuit, no bad led indicator ,no high voltage, no low voltage, no ... etcVisual full inspection: to make sure no scratched case, no cracked wires ,no missing screw, no label misaligned, et 3 sampling inspection:IQC ... 20 second. To make sure no bomb unit, every unit work at normal temperature, etc 2 pin plug 5v 2a micro usb ...