Simple twist operation: all you have to do is rotate it and the numbers will be +/-, with a minimum unit of 5 seconds. 1 key operation, press the ST/SP key on the screen to start or stop counting. Metal Knob: Unlike other timepieces, the outer ring is made of aluminum alloy, which is more durable and easy to clean. The design is inspired by the dashboard of the car, which is more elegant and technological. Large LED Screen/Large Digits: The black screen and the white numbers provide a strong contrast for easy viewing. The 3-inch large screen and oversized figures lighten the burden on your eyes. 99 Minutes Countdown Timer: Digital timer counts down from 99 minutes 55 seconds to zero, or counts down from zero to 99 minutes 55 seconds as a stopwatch. Constant Light/Energy Saving: Our cooking timer has 2 brightness modes: 1. Brightness is constant; 2. The number dims after 5s, and power off without operation after 5s to save power. MORE USAGE: Great for kitchen timers, exercise timers, egg timers, oven timers, homework timers, game timers, and more.