The EcoMill is a completely self-powered treadmill that provides a unique green alternative to motorized treadmills. Utilizing an innovative curved running surface, this manual treadmill has been proven to burn up to 30% more calories than motorized treadmills, engaging more muscles for an overall superior workout. The best part is the onboard generator system that produces power for the display and can even be used to charge a phone or iPod with the USB charging station!