: The SW1-R’s optical smoke sensing chamber ‘sees’ smoke as it enters the alarm, reducing the likelihood of false alarms. It is ideal for slow-burning fires that produce thick white smoke. The SW1-R smoke alarm functions perfectly as a standalone unit but can also be hardwired and interconnected with up to 12 mains-powered smoke (SW1), heat (HW1), or carbon monoxide (CW1) alarms.
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