This teaching clock is a 40cm diameter and shows both 12 & 24 hour times. All the minutes are clearly graduated to help children learn to tell the time and understand the concept of minutes and hours. There are 4 magnets on the back for fixing to whiteboard type surfaces and a hook so it can be hung. The two hands are geared correctly so that as one hand turns, the other moves the proportionally correct amount. It is recommended to combine this set with #1190P to help children be part of the fun.