1. Do not use excessive force when turning to the end to avoid damaging the built-in clockwork;^ 2. If the timer works, do not repeat the rotation back and forth to avoid damaging the built-in clockwork.^ 3. The timer shell is made of ABS plastic. Please do not throw, throw or smash the shell, which can easily damage the timer.^ 4. The timer bowl and built-in clockwork are all made of plastic, please do not use fire for baking or burning. Tip 5: first set the timer to the 30 or 50 minute mark and then set it back to the desired time. That makes them more impact resistant, more durable, more accurate and more attractive.^ No battery required: the spring-wound timer does not require a battery. When the mechanical clockwork reaches the set time, the bell will ring automatically.