[Correct usage]: No.1. Before use, turn the timer knob clockwise a full circle, starting from 0 to 0 (0-10-30-55-0), No. 2, and then turn counter-clockwise to the desired time. When the countdown is over, it will play a sound. If the above method is not followed, the timer may not sound [Mechanical-Manual]: the mechanical timer does not need batteries. Just turn the timer knob manually. The operation is simple and practical. It is suitable for cooking and guiding children's homework [Suitable for many occasions]: Our visual analog timer can be used for many occasions, it helps teachers to divide students' school time effectively; it is also a great helper in managing working time in the office. [TIME MANAGEMENT]: A 60-minute learning clock helps you organize and focus on tasks. The desk timer is ideal for children and adults to improve time management and productivity while completing activities With a built-in 70db alarm, this visual timer has a ringing range of up to 49 feet. Mechanical stopwatch alarm lasts 5 seconds and CAN in the other room. [Easy to use] Not sure where to put this visual timer? Don't worry - this kitchen timer has strong magnets that allow you to place it on metal surfaces like the fridge or oven. [Easy to use] Our clock timer does not require batteries to operate. Turn the magnetic timer clockwise for 55 minutes until the dial turns red, then turn it counter-clockwise to your desired time.