Requires 5-7 business days for processing. Monitor your pedaling cadence as you ride with this self-calibrating, wireless speed/cadence sensor. It measures and reports your pedaling strokes per minute, providing feedback for optimal performance. The GSC 10 is compatible with the Edge 305, Forerunner 50 and Forerunner 305 only. Please Note: This item has been built to U.S. electronics specifications and may need additional modifications or converters to be used in countries other than the U.S. and Canada.