A small change can make a big difference. Match your mood and style with vibrantly colored, easy-to-change wristbands. The durable silicone wristband of the waterproof A300 is light and comfortable to wear. Every jump, skip, hop, walk and run counts. The A300 shows your steps, distance, and burned calories, and motivates to reach your activity goal. If you stay still for too long, the A300 will vibrate telling you it?s time to move again. Train to your own beat with Polar H7 heart rate sensor and make sure your every move is counted for. Finish strong and feel great! Complete each training by analyzing results in Polar Flow web service and app Getting enough quality sleep is important for your wellbeing. The A300 automatically clocks both the moment you start sleeping and wake up, and wakes you up with a gentle vibration. Follow your sleeping patterns in Polar Flow to find the right balance of training, daily activity and rest.