Review on COOSPO Bluetooth & ANT+ Heart Rate Monitor Armband - Optical HRM Sensor, Waterproof IP67, Fitness Tracker Armband Compatible with Zwift, Wahoo Fitness, Endomondo, Peloton - Includes One Extra Free Armband by Angel Cortez

Effortlessly lowers heart rate then recovers heart rate while cycling (one at 150s, the other at high 70s). in various places on my arm and wrist and in the beginning it tracked my heart for about 2-3 minutes but then lost my heart and numbers which was literally my bike rate. I probably feel a slight movement of my hand while cycling, but my heart rate oscillates somewhere between a high 140 and 160 after 15 minutes, while that reading is 70 and within 1 of my cycling cadence displayed on my exercise bike. Somehow he loses his pulse and notices my slight hand movements. After 3 attempts it was sent back.