This heart rate monitor is as unobtrusive as a class ring and provides pulse readings without an uncomfortable chest strap. The device simply slides on your index finger and displays an EKG accurate reading on its LCD with the touch of a button. The heart rate ring can be set to audibly alert you when your heart rate exceeds or falls below a preset optimal beats-per-minute target zone, informing you when to increase or decrease your pace. The device also calculates calories burned, steps taken, and distance traveled. With stopwatch and clock functions. Includes one CR2032 battery. 1" L x 1" W x 1" H. (5 oz.)