Ringside High Intensity Interval Timer Used to increase speed, power and endurance The High Intensity Timer's pyramid shape allows it to be easily seen even in the busiest gym Red and green lights on the top indicate work and rest periods for the rounds, while yellow and blue lights on the face of the timer indicate high and regular interval periods Round lengths can be set to 1.5, 2, 3, 4 or 5 minutes in duration Rest seconds can be set to 15, 30, 45 or 60 seconds