What's on the ceiling of the hotel?

Call the police if there is smoke. Generally, cameras are not installed, which is illegal, so don't worry. Smoke detector: If there is a fire, these things will start automatic water spraying when they sense smoke. The smoke detector can detect a large amount of smoke produced in the fire and send out an alarm signal in time. The detector is controlled by a single chip microcomputer, which can intelligently judge the smoke generated during the fire and give an alarm. The alarm adopts photoelectric smoke detector and excellent production technology, which has the advantages of stable operation, beautiful appearance, simple installation and no need of debugging. Can be widely used in hotels, shops, Internet cafes, dance halls, cafes, leisure halls, residential and other places of fire safety monitoring. The alarm has a built-in buzzer, which will make a strong sound after the alarm. The alarm is powered by 9V laminated battery, which consumes little power and can be used continuously for more than one year.