The FireAngel SW1-R Optical Smoke Alarm in white is a reliable and essential safety device for any home. With a photoelectric smoke sensor and battery backup, this alarm provides peace of mind knowing your home is protected against potential fires. The model features a 4.5 cm diameter and operates with a power source of battery and hardwired. The FireAngel SW1-R is a trusted brand known for its quality and effectiveness in detecting smoke quickly, ensuring a safer environment for you and your family.