The Garmin Foot Pod. This tiny foot Pod is small enough to attach to your shoelaces or Fit in the mid-sole pocket of compatible shoes. It's always ready to use, and a small, replaceable watch battery powers the foot Pod for a year of training. Unlike simple pedometers, this foot Pod Uses advanced MEMS inertial-sensor Technology to analyze your movements and is responsive to stride-length changes to achieve 98 percent accuracy for speed and distance. Additionally, this sensor measures running cadence to help you optimize your training. Features of the Garmin Foot Pod Monitor your distance and cadence when indoors Provides distance and cadence data when used with the FR70 series Uses advanced MEMS inertial-sensor Technology