TWENTY5 SEVEN Countdown Timer 7.5 inch; 60 Minute 1 Hour Visual Timer – Classroom Teaching Tool Office Meeting, Mechanical Countdown Clock for Kids Exam Time Management Magnetic, Sky Blue[ Visual Sky Blue Disc ] As time elapses the sky blue disc disappears. Large enough to see from a distance. Easy to keep track of time. Helps even the youngest to understand how much time is left. [ Mechanical Timing ] You never need to replace batteries. Make sure to wind up the timer every time before setting countdown minutes. [ Loud Audio Alerts ] Making it clear when time has expired. [ Ideal Time Education Tool ] Best tool to help children