With the Polar H7 heart rate sensor you will easily measure your heart rate while training. The reading can be displayed on a compatible smartphone device thanks to a Bluetooth connection and will let you asses the intensity of your workout. The heart rate sensor provides low energy consumption and reliable performance. It will fit you perfectly thanks to a comfortable and discreet belt. The Polar H7 heart rate sensor is compatible with iPhone 4S, iPhone 5, iPod touch (5th generation), iPad (3rd and 4th generation), iPad mini and iPod Nano(7th generation). In addition, it comes with a 2 year warranty.