Wireless sport earbuds that not only play your favorite music but also keeps track of your activity. It will calculate your steps, distance covered (with GPS function to track your route) and calories burned to give insight to your work out. The heart rate sensor will monitor your fitness level and help you to improve your performance. Including free APP to upload your data. With built in 100 mAh battery that allows you to use the gadget up to 5 hours. Bluetooth version 4.0. The App is compatible with IOS 9.0 and Android 4.4 and higher. Max print size : 25 x 10 mm