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
Battery Replacement Instructions for Premium Feature HRM Straps | Garmin Customer Support
Garmin Fenix 3 - Garmin: Replacing the Battery in your Heart Rate Monitor ( HRM) The CR2032 batteries in your HRM-Run, HRM-Swim or HRM-Tri straps will last approximately 18 months, depending on use.
Garmin HRM-Dual™ | Heart Rate Monitor with Chest Strap