Accurately monitor your heart rate with the Polar Verity Sense Heart Rate Monitor Armband Black S-L. You can wear this arm band on your upper or lower arm. You can easily adjust the arm band to your arm circumference, so the monitor is always tight. The heart rate monitor is waterproof and suitable for fanatic swimmers. That's because of the included clip. With the clip, you can attach the sensor to your swim goggles. That way, you can measure your heart rate via your temple. You can connect the heart rate monitor to your smartwatch via Bluetooth. Or you can use ANT+ to connect the Verity Sense to your smartwatch, sports watch, or fitness machines. This way, you can easily view your heart rate on your sports watch when you're working out. After your workout, you can view your heart rate information in the Polar Flow training app.