LOWEST EVER PRICE (CAMEL X3)
I've posted these before at 6.79 but now even cheaper!
And a must have for any home/office.
Optical Photoelectric sensor
10 year long life operation (No need to replace battery)
Early silent low battery warning
Reduced sounder output for testing
Hush Test/Reset buttons
(and don't get me started with the "free ones I could get from my local fire brigade" parasitic nonsense, -rant over...)