The Reebok Precision Trainer Heart Rate wireless strap is a high-quality heart rate monitor designed for gym and training activities. With features such as a calorie monitor and fat monitor, this model (Precision Trainer XT) provides accurate measurements of heart rate to help users track their fitness progress. Whether you are working out at the gym or training at home, this wireless strap offers a convenient and reliable way to monitor your heart rate and stay on top of your fitness goals.Might need a $3 battery