Viiiiva

Trusted by pros and enthusiasts alike, Viiiiva is 10x more sensitive than most heart rate monitors, 5x more responsive, uses advanced beat-to-beat measurement, and can store up to 65 hours of data. The sensor also collects and transfers data from your other ANT+ products via Bluetooth to your iOS or Android device.

Viiiiva is comfortable and easy to wear, featuring a soft, flexible strap for a perfect fit.