COOSPO Bluetooth Heart Rate Monitor Chest Strap H808S, ANT+ BLE HR Monitor Chest, HRM IP67 Waterproof, Use for Running Cycling Gym and Other Sports H808S Black
Amazon.com : COOSPO Heart Rate Monitor Chest Strap H9Z, Bluetooth 5.0 ANT+ Heart Rate Monitor Chest Sensor with Rechargeable Battery, HRM Works with Strava/Wahoo Fitness/Polar Beat/Peloton/Zwift/DDP Yoga App : Sports & Outdoors
Troubleshooting your heart rate monitor/strap HR spikes | DC Rainmaker