The MZ-Switch, from Myzone is a versatile heart rate sensor that delivers dual HRM function for more accurate heart tracking. One is a PPG sensor, like Apple Watch, the other is ECG. The Switch can be used in three different ways, depending on what exercise you’re doing. Wear it on the wrist for sports like running & swimming & then “Switch” & use it as a chest strap on the stationary bike or for lifting. Connects seamlessly with Strava, MapMyRun, and Apple Health.