Forerunner 920XT - Replacing the HRM-Swim Battery and the HRM-Tri Battery
A look at Garmin's new swimming heart rate straps: HRM-SWIM & HRM-TRI | DC Rainmaker
Amazon.com: Garmin Swim 2, GPS Swimming Smartwatch for Pool and Open Water, Underwater Heart Rate, Records Distance, Pace, Stroke Count and Type, White & HRM-Swim Heart Rate Monitor : Electronics