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
Garmin Hrm Pro Tri Heart Rate Strap Run 4.0 Swimming Running Hrm-dual Ant+ Bluetooth Bike Bicycle Cycling Computer Gps Hrm4-run - Bicycle Computer - AliExpress
Introducing HRM-Tri™ and HRM-Swim™ - the first heart rate monitors from Garmin® designed for use underwater - Garmin Blog