FT4 heart rate monitor provides a smarter training experience. Whether your goal is to lose weight or improve your fitness, Polar's easy-to-use heart rate based Smart Coaching features will guide you to exercise efficiently and motivate you to reach your fitness goals. The FT4 provides continuous, accurate heart rate and lets you know exactly how many calories you've burned. In addition, it stores your last ten training sessions so you can track your progress. Requires and includes comfortable fabric heart rate chest strap (adjustable size M-XXL). Operational Instruction: Getting started with a Polar heart rate monitor is easy. First, make sure you thoroughly wet the electrodes on back of the heart rate chest strap with water and snap the transmitter into place. Then place the strap on your chest prior to starting the watch. Tip: it is best to stand away from others when starting the watch. When you are finished with your workout detach transmitter, rinse the strap with water and hang dry.