wireless security system home
6 stars at Home Depot, but that's only based on around 20 reviews across the two sites. The First Alert SA521CN 3ST Est. $40 is a hardwired version of the battery operated First Alert SA511CN2 3ST/SA511B interconnectable smoke detector. The two First Alert smoke detectors can be mixed and matched to create a smoke detector network that covers your premises. If you have a pre existing interconnected hard wired smoke detector network, a First Alert SA521CN 3ST sometimes sold as simply the First Alert SA521CN can be substituted for one of the existing units to act as a bridge so that when one smoke detector is activated, all smoke detectors on both networks will sound an alarm. This can be an effective way to integrate new, interconnected photoelectric smoke detectors with an existing hard wired interconnected ionization smoke detector network for protection against all types of fires. The alarms are also compatible with interconnectable First Alert CO and combination smoke and CO alarms, such as the First Alert SCO501CN 3ST Est. $50, which is covered in our section on combination smoke and CO detectors. Both of these smoke alarms use wireless technology to create their interconnected network. If you already have a wired network in place, the First Alert 7010B Est. $20 is a photoelectric smoke detector to consider.