the problem is finding the "procedure"! This is actually anti-ergonomic want to hide a laser button in an impossible position to find and then light still pressing "some time"! Come on, I give it the solution: - We must remain supported on the outer wheel at about 315 °, ie to the location of a needle shows at 10 am and stay at least 4 seconds! - The loupiote battery lights, as if the mouse was discharged! do not panic, it is still responsible but loupiote wants 'simply' say you have managed to put "ON" the laser button. - Use the laser button by pressing the center button !!!