A:Answer Underside of mouse, Best Buy Essentials tag to the right, there is a little compartment on the left side. Pull the little tab to open the compartment and remove the top battery. There is a silver pull tag that removes the bottom battery. Replace with fresh batteries in the same sequence making sure to keep the pull tag available for next time. (must be on top of lower battery) If you lose or break the pull tag, you can use a small pocketknife or screwdriver to remove the lower battery.
