The Time Timer 20 MIN packs all the features that have made our visual timers the first choice of teachers, students, parents and professionals into a new 20-minute timer. The Time Timer 20 MIN offers a greater visual impact for shorter duration needs such as completing blocks of homework, silent reading, instrument or sports practice, as well as perfectly managing the 15- to 20-minute work cycles in elementary education. The Time Timer 20 MIN is the new secret weapon for workplace meetings with 15- and 20-minute agenda items to keep each item on track and works perfectly when starting an organizing project at home. And, it's the ideal visual timer for 'stand up' meetings in software development to keep on time. Sometimes an hour is too much time, the Time Timer 20 MIN makes it easy to visualize how quickly 20 minutes will pass by. Benefits-Teach children the concept of elapsed time-Make homework and practice time more productive-Keep meetings on time and moving forward-Reduce conflict in family and household routines-Manage the stress of transitions by showing " how much longer" -Empower teachers to teach instead of constantly monitoring behavior-Increase performance on tests and in the workplace-Transcends language and culture barriersFeatures-Volume control dial for those times you need a louder tone and those when you prefer silence.-Easy-to-read numbers-Lightweight anti-static disk-Silent operation (no loud ticking.)-Size: 5.5" x 7" -One AA battery required for operation (not included)