iFit Wireless BlueTooth BLE Heart Rate Monitor - Treadmill Doctor
DUAL ANT+ / Bluetooth Smart Heart Rate Monitor Belt KALENJI | Decathlon
SportPlus Bluetooth 4.0 Chest Strap Heart Rate Monitor for iOS (From 7.1), Android (from 4.3) and Windows Phone, Optional with ANT+ And 5.3 Khz : Amazon.co.uk: Sports & Outdoors