All of the Microsoft L Cellphone goods 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 microsoft batteries can be passed easily through the test of short-circuit, over voltage, low voltage etc. And our microsoft battery has been tested on related microsoft Cellphone to ensure that them are 100ompatible original product. In addition, we also provide 30 Days Money Back and One Year warranty to ensure your confidence with our microsoft Cellphone batteries. We look forward to cooperating with you!