Apple Watch Nike SE GPS, 44mm Space Gray Aluminum Case with Anthracite/Black Nike Sport Band - Regular - Walmart.com
Nike Run Club / AppleWatch / Polar BT HR monitor - experimentation | MacRumors Forums
Amazon.com : Heart Rate Monitor Chest Strap, iGPSPORT HR40 ANT+ and Bluetooth Waterproof HRM Sensor Compatible with Bike PC, Peloton, Zwift, Wahoo, Real-Time HR Data and Movement Dynamics in Exercise : Sports