The optical smoke alarm makes protecting your home simple. Its optical sensing chamber 'sees' smoke as it enters the alarm, providing a fast response to slow burning fires with thick white smoke. The advanced optical sensor ensures the FireAngel smoke alarm is less prone to false alerts from cooking fumes. Avoid placing near bathrooms or kitchens. Each smoke alarm is fitted with a 10-year sealed battery, offering protection for the lifetime of the device without needing to change the batteries. Fitted with a removable base plate, secure it to the ceiling using the screws provided. Push and twist to secure the device. The FA6620 smoke alarm holds CE and UKCA marks and is certified to BS EN 14604:2005+AC:2008. Suitable for domestic premises, including leisure accommodation vehicles, it comes with a 5-year warranty.