General:The 20/20/20 Rule for screen time, reading, and other strenuous eye activities states that every 20 minutes, we should look 20+ feet away for 20+ seconds to reduce the effects of eye strain and to protect our eyesight over time. In addition to the 20/20/20 Rule, performing daily eye relaxation exercises can keep your vision sharp and prevent unnecessary eye strain. If youre new to eye relaxation exercises, you can start by looking up The Bates Method.This information is provided for informational purposes only and is not intended as a substitute for professional medical advice, diagnosis or treatment.Single Interval Timer:This timer can be used in 20 minute intervals, or at another desired time interval, to alert you when it is time for a vision break from screen time, reading, etc.Pomodoro Style Timer:This timer comes with preset and customizable time interval settings to allocate vision breaks throughout longer work sessions. This is a hassle-free way to set multiple timers at once that span your entire working period. Make sure to press the Start button at the beginning of each new interval. When manually entering timer values, click the check box on your keypad before clicking the Start button.