The Hobie Mirage Speedo lets you measure your pedaling speed. The removable pitot tube speedometer measures your pedaling speed in miles per hour. The readout may vary depending on the weight in the boat, but it is very sensitive and will be able to accurately tell you if your speed increases or decreases. The Hobie Speedo fits older Mirage Drive systems made between 2001 - 2009. It will not fit any V2 or GT Mirage Drives.