Description [Correct use method]: No. 1. Turn the timer knob clockwise one full turn before use, starting from 0-0 (0-10 -30-55-0), No. 2, then turn counterclockwise on a clock until the desired time. When the countdown is over, it will make a sound. If the above method is not followed, the timer may not ring [Mechanical-Manual] The mechanical timer does not need batteries. Just turn the timer knob manually. The use is simple and convenient. It is suitable for cooking and monitoring children's homework [Suitable for many occasions] Our visual analog timer can be used in many occasions, it helps teachers to allocate students' school time effectively; it is also an excellent assistant for managing office work time; [TIME MANAGEMENT]: 60-minute learning clock helps with organization and focus between tasks. The desk timer is great for kids and adults to improve time management and productivity during activities. With a built-in 70 dB alarm, this visual timer has an audible ringing range of up to 49 feet. The mechanical stopwatch alarms for 5 seconds and can be heard in another room. [Easy Access] Not sure where to place this visual countdown timer? Don't worry - this kitchen timer comes with strong magnets that allow you to place it on metal surfaces like the refrigerator or oven. [Easy to Use] Our timer requires no batteries to operate. Simply turn the magnetic timer clockwise up to 55 minutes until the dial turns red, then turn it clockwise.counter-clockwise to the desired time.