The bike computer kit is your personal on cycle data processor. It can measure your speed, distance, calories burned but it is so much more than a speedometer. It measures the temperature, honks a little buzzer and control LEDs to light your way and stylize your ride! Totally open-source and hackable, the bike computer is built on top of the awesome arduino platform so you can program it to analyze your biking data any way you like. Powered by 3 AAA batteries or rechargeable lithium.