The RSDUALP Dual Power Smoke Alarm combines 240V mains power with a 3V battery that lasts for 10 years, ensuring reliable performance and extended coverage. It features a 140mm slide base for easy installation and supports both hardwired and RF module interconnection for versatile setup options. Additionally, it includes a dual mesh insect guard to assist in the prevention of false alarms caused by insects. This provides enhanced protection and peace of mind. RF module not included and can be purchased separately.