Over-current protection, Voltage protection, Short circuit protection, Hot seller,Price advantage. Laptop adapter:Input :100-240V 50-60Hz 1.5AOutput:19V2.1ADC ... patch technology production;2, Allmported electronic components, circuit boards with over-voltage, over current, short circuit protection;3, Output power enough;4 ... % compatible with original power supply. 40W 19V2.1A for laptop adapter