The Cateye Velo Wireless Computer packs a punch with a programmable odometer and menu screen. It installs easily on almost any bike, including 27.5 and 29&';ers. Battery: 1, CR2032 Lithium Metal, 3(V), 0.735(Wh), 0.3g, Included Computer functions: Current/ average/ maximum speed, trip distance, total distance, elapsed time, clock, calorie consumption Analog wireless computer Pace arrow Simple tire size Auto start / stop Programmable odometer Menu screen to change setting Includes zip tie bracket