POLAR H10 Bluetooth Smart HR Sensor (M-XXL) – The Wearables Store
Amazon.com: Udoarts Heart Rate Monitor with Chest Strap for iPhone,Android Phone,Wahoo,Polar Suunto Garmin,Man and Woman,Bluetooth4.0&ANT+ : Health & Household
Polar H9 - Heart Rate Sensor for Cellular Phone, Smart Watch, Activity Tracker, Medium, Double Extra Large - Walmart.com