Listen up to hear your heartbeat, then calculate your pulse rate! Offers so-simple operation: Place the monitor over your heart and hold the button for a few seconds to hear the audio computation of heartbeats per minute Helps students reach a deeper level of understanding as they engage all of their senses Supports human body and health lessons, as well as physical education classes Measures 4″L x 4″W x 2″H Requires 3 AAA batteries, not included Grades K+