Sand timers 3 minutes Colour coded large sand timers provide a fun and easy way to measure time, Sand timers help teach the concept of time as sand passes through one chamber to the next. Perfect for use in games and timing experiments. Sand timers help sharpen concentration and ease stressful transitions both in class and at home. See how much time, at a glance, is remaining during a lesson, activity, or therapy session with no disruptive alarm. Virtually indestructable, including moulded end caps and thick plastic walls. Large Sand Timers measure 16cm high and 7cm wide.