SUUNTO t4c Heart Rate Monitor and Fitness Trainer Watch (Black Volcano) 100% Nylon Versatile heart rate monitor watch in contemporary "black volcano" color Displays current heart rate, average heart rate, and calories burned Training Effect function measures how hard your body is working Suunto Coach mode lets you create personalized 5-day training workout Interference-free digital ANT transmission; water-resistant to 100 feet; 2-year warranty