... 2.short circuit ,over voltage protection 3.Warranty:24 months wall mount 220v 120vac to 24v 12vdc power supply : Input Voltage100~240VOutput ... short-circuit, no open circuit, no bad led indicator ,no high voltage, no low voltage, no output, etc Assembly full ... missing screw, no label misaligned, etc2 sampling inspection:IQC (incoming quality control): according to AQL-MIL-STD-105E level II standardOQC ...