The ultimate tool in communicating the concept of elapsed time. Ideal in education, for special needs, meetings, panel discussions, presentations and more. Simply move the red disk counterclockwise to the desired time interval. The disk diminishes as time elapses until no red is visible on the timer face. The disk may be gently moved clockwise or counterclockwise without harming the mechanism. Set at any point 0 to 60 minutes. Quartz movement. Uses one "AA" battery. You have the option to use a visual depiction only, or add sound to signal the end of a time segment. Comes with a base for free standing operation.