length of timer interval can be set to any length from 3 seconds to 3 hours exact number of repetitions can be set or the timer can repeat forever, until the user stops it add breaks between the intervals if you want! you can choose a pause from 3 seconds to 30 minutes. So it's perfect for an interval training (for example 5 minutes activity -> 30s break -> 5 minutes -> 30s -> etc... add metronome if you want! Keep the requested pace/rhythm. It's useful for example while cycling or fitness bac