The Red portion shows how much time is left and the user will visually see this red portion reduce as time passes. The Large Time Timer is designed for classroom and group activities. The large size and bold dial numerals also make this timer easier to read for visually impaired users. This model can be wall hung for use by multiple individuals. N.B. as this timer has moving parts, to get proper function you must use strong batteries. This timer has an audible beep at the end of the set time. The beep may be turned on or off as required.