Fully-approved and practical, Kidde's hallway or landing smoke detector 0918UK has an escape light to illuminate the route. A hush and test button let you check its operation and, just in case, it has a low battery indicator bleep. It is made by Kidde and has a 5-year warranty. The battery is included.
Suitable for hallways and landings
Do not use in or near to a kitchen or shower room
Fixing requires two little screws and wallplugs (included) to screw to ceiling or use sticky pads | 
