Pioneer has created the first, and only, power meter that measures power output and pedaling stroke efficiency for each individual leg, in real time, so you can analyze and adjust your technique while you ride. At the heart of the Pioneer Power Meter System are two streamlined strain gauge monitors that can detect the slightest tangent and radial force direction as power is applied to the crank arms. This proprietary system detects the amount and the direction of force at 12 different points in each pedaling stroke for each leg.