Visit the Pace Band FAQ for more information.
Elevation Band Size:
Measure around your wrist to determine the size of your wrist in inches. The band size is the actual circumference it will fit. For example, if you had a drinking glass that is 7" around (circumference), a 7" pace band will fit around it exactly.
Fit is a personal preference. Some people like it loose and some people find it more comfortable with a snugger fit. Keep in mind is that the tighter the fit, the more difficult it may be to rotate the band while running in order to view all the splits - especially when your wrist gets wet. Also, if you are wearing long sleeves, consider whether you will wear the Pace Band under or over your sleeve.