Fun and Fitness Health System for Kids Happy Bike keeps children moving offering an activity based recreation and promotes a healthy lifestyle. Manual operation for safety. Sturdy frame is made of powder coated steel. Some pieces have foam wrap over the metal tubing. Offers a multi function battery operated, (2AA not included), monitoring system. Digitally displays time, speed, distance, burn calories, and total distance. Tension and seat height adjustment. Monitor includes an auto on and shut off when no activity.