Wired smoke and carbon monoxide detector that only use an annoying beep and a blinking light to say something's wrong, the Nest Protect delivers specific insight into the conditions in your home. Choose the wired Nest Protect if your old smoke or CO alarm has a green LED and connects to the wires in your wall or ceiling. Easy to install, it automatically connects to the other Nest Protect devices in your home. A green glow will indicate that everything is okay, while a yellow glow provides an early warning for small amounts of smoke, and a red pulsing light indicates a more serious emergency. Connects to your WiFi network, so you manage your Nest Protect from your phone and receive alerts. White. 2-year warranty on parts.