Wireless mouse must use battery. Wireless mouse packaging will come with a battery, find the mouse battery cover to install the battery, pay attention to the battery into the positive and negative direction of the correct, close the battery cover. The battery compartment of most wireless mice is designed at the bottom of the mouse, pay attention to check whether there is a switch button of the battery compartment at the bottom of the mouse, if not, directly press down gently with your thumb, and then push the battery cover back to open the battery cover; Another such as Logitech M215 as an example, its battery compartment is designed at the rear of the mouse, and the battery compartment button is at the bottom of the mouse.