What does heart rate monitor do & how does it work on smart watch?
Fitbit Charge 2 Heart Rate + Fitness Wristband All Colours
Smart Watch For Sports Health Monitor Temperature Heart Rate Fitness Tracker UK | eBay
Activity Trackers for Women Men 1.1''AMOLED Screen Fitness Watches with Heart Rate Blood Pressure Sleep Monitor Calorie Tracking Step Counter Smart Band for Android and iPhone: Amazon.co.uk: Sports & Outdoors
Smart Healthcare Watch With Ecg Heart Rate And Blood Pressure Monitor | Robert Dyas
ID115HR PLUS Smart Bracelet Sports Wristband Fitness Tracker Heart Rate Monitor - Black - K&F Concept
Waterproof Health Tracker,MorePro Fitness Tracker Color Screen Sport S– Tikker Watch
Smart Watch for Women Men, Fitness Tracker with Heart Rate Monitor, Activity Tracker, Step Counter, Sleep Monitor, Calorie Counter, IP68 Waterproof Smartwatch for Andriod IOS (Black): Amazon.co.uk: Electronics & Photo
Smart Watch Bracelet Fitness Tracker Temperature Heart Rate Steps AMOLED Black | eBay
Fitbit Charge 2 Heart Rate + Fitness Wristband All Colours