Cavius Longlife Photoelectric Smoke Alarms 2 Pack

With a 40mm diameter, this is the smallest photoelectric smoke alarm in the world. Ideal for bedrooms, lounges and hallways, this alarm takes optical readings every 8 seconds, ensuring it is always on the lookout for smoke. It's powered by a sealed-in Duracell lithium battery that lasts for ten years, after which the alarm should be replaced. Install either recessed (19mm profile) or flush (44mm profile) to suit your home.