The PSA Lifesaver Silhouette 5800ACF is a low profile mains powered photoelectric smoke alarm that operates on a 240V power source with a non-removeable 10 year lithium battery backup. This advanced smoke alarm is flush mount design only 110mm wide x 28.5mm high installed. The single piece construction is easily installed in a 90mm hole cut-out. The dual insect screen design reduces nuisance alarms from bugs and insects. Features: Low profile flush mount design Photoelectric Sensing Technology. 240VAC with sealed 10 year lithium battery backup, no longer need to change battery. One button Test and Hush feature Large easy design button to Test alarm operation and Hush to silence nuisance alarms. Two LEDs. – Green LED indicates AC condition. – Red LED indicates alarm condition. Alarm memory. Dual insect screens over outer perimeter and inner sensor chamber to reduce nuisance alarm. 90mm cut-out, down-light style mounting for quick and easy installation. Compatible Interconnect with the PSA Lifesaver range of smoke alarms and accessories.