All of the machenike laptop adapters have the protection function of over charge and over discharge, over heat, over current etc. We have passed the CE authentication of Europe, and it produces according with the UL standard, all of machenike adapters can be passed easily through the test of short-circuit, over voltage, low voltage etc. And our machenike adapter has been tested on related machenike laptop to ensure that them are 100% compatible original product. In addition, we also provide 30 Days Money Back and Two Year warranty to ensure your confidence with our machenike laptop adapters. We look forward to cooperating with you!