Everlast Personal Boxing Timer * Workout times and rounds can be adjusted for either 2 or 3 minutes and from 1 to 12 rounds with 30 to 60 second rest periods in between rounds * Built in ring gong and silent vibration features alert you of the end of each round Personal Round Timer- Adjustable Round Lengths-Audible Ring Gong and Silent Vibration Alerts- Batteries Included- Great way to maximize your workout and not focus on how long you have been doing an exercise, it automatically gives you notice that your time is up. Help regulates your workouts.