This classic AccuChef timer times up to 60 minutes with one minute increment. It’s easy to use and understand by all ages. The timer works when you turn the timer knob clockwise to the 55-minute mark and then turn counterclockwise to the desired minute mark to activate the mechanism. The alarm will ring when the pointer reaches zero. This timer can be used for baking, cooking, as a classroom timer, study timer, toddler timer, for improving time management, etc. and it provides a great visual for children to understand the passage of time. We provide a two-year warranty against defects in material or workmanship. This unit does not require any battery to operate.