There are many benefits of having the Onelink Combination Smart Smoke and Carbon Monoxide alarm. One reason being is the fact that it helps protect for the lifespan of 10 years against both deadly threats in one unit. This alarm has sensing technology that works actively to help better protect you and your loved ones. It also contains the wireless interconnect feature which allows you to connect each of your First Alert Onelink alarms so when one alarm sounds, they all will sound. When seconds count in an emergency it provides an audible indication of the possible threatened area and more importantly what area to investigate or to avoid. Another benefit of this product is that it contains Bluetooth and Wi-Fi connection so you can be connected to your home even if you are away.