NO BATTERIES REQUIRED - Completely mechanical countdown timer for school classroom office working kitchen cooking gym body building and more High accurate mechanical timing No batteries needed Durable for years IDEAL TIME MANAGEMENT TOOL - Improve time management increase productivity with daily tasks and more Examples test taking managing playtime bedtime routines setting timeouts and making sure teeth are brushed long enough Excellent timer to help children understand the passage of time visually Recommended for parents and teachersespecially special education and K-12 teachers It is not intended for use by children FOR SPECIAL NEEDS - The countdown clock can help those with special needs As the time elapses the bright colored disc disappears The visual design of this timer helps ease transitions and encourages independence and increased productivity for people of all abilities SMALLER FOOTPRINT WITH MULTIPLE PLACEMENT OPTIONS 1) Features powerful magnetic backing panels making it ideal to place on refrigerators ovens utility cabinets classroom whiteboards and more 2) The two foldable legs on the backing canup for placement on flat surfaces like desks and countertops 3) The hanging hole is for easily wall mounted EASY TO USE To activate the timer before EACH USE turn the control knob clockwise to the 55-minute position then turn it counterclockwise to the desired time Size is 6.3 x 6.3 x 2.0 inches Large enough to see from far distance of how much time is left. There is a gentle ticking sound that lets one know the timer is working.