waterproof and analog bike computer with speedometer and odometer. This retro bike computer stands out because it does not require a power supply, which saves both costs and the environment. There is also no risk of discharged batteries as this bike computer is built to last. It is also easy to use thanks to its mechanical drive system and shows a speed of up to 60 km/h, the number of revolutions, and the total distance. The bike computer is powered by a cable that is connected to the front hub just behind the fork - the shock absorber. The end of the cable is connected to the spokes, when the wheel spins, the gear starts to rotate the cable and makes the mechanism work. The mounting is gentle on your bike thanks to a rubber mount that prevents scratches even on uneven roads. Regardless of the weather, the bike computer's waterproof construction is a reliable companion on your bike rides. Universal design thanks to adjustable screw mount Retro design without power supply Material: Aluminum Size: 98 x 12 x 8 cm Cable length: 78 cm Fits (wheel size): 26", 27.5", 28", 29" Included: Meter, Cable Simple mechanical operation Waterproof and durable Shows speed and distance