Garmin HRM-Dual - Premium Heart Rate Monitor Chest Strap, Real Time Heart Rate Data via Bluetooth Low Energy, ANT+, Black : Amazon.co.uk: Sports & Outdoors
Digital Heart Rate Monitor Chest Belt - hrm ant+ / bluetooth - Tunturi New Fitness B.V.
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