The calling watch has arrived to facilitate the process of calling students for departure from school to avoid crowding and standing in the sun. It has many uses. It works through a wireless remote. With the press of a button, the watch emits a buzzing sound and also vibrates. Its battery lasts from 24 hours to 72 hours depending on usage. If you use it during school hours and then turn it off, it will last for two weeks. It is not waterproof because it has a charger port. It comes with a one-year warranty on manufacturing defects. The available quantity is sky blue.