Bought 3 of these to replace a very old smoke detectors that were built-in to our very old alarm system. Very easy to install & set-up (already had a Nest account). So far they are great. I like how they are both smoke & carbon monoxide detectors. I like how they are motion sensitive & can work as night lights. But best of all I like how they all work together & are connected to your smart phone app. Totally worth the price for feeling safe.

This smoke detector is modern, sleek, practical, and integrates quite seamlessly within our ecosystem of Nest home products. Only gripe is the price. $150 for a smoke/CO detector is quite hefty but the key feature to appreciate is to be alerted on my smartphone in the situation where I am not home. You won’t get that functionality with a regular standard smoke detector.

Nest Protect Smart Smoke/Carbon Monoxide Alarm provides the ultimate protection & peace of mind. The intelligent alerts discriminate between steam and smoke. A clear "Heads Up!" pre-alert gently cautions you in situations when close proximity to steam or a little smoke in the kitchen, for example, is about to trigger an alert. You can silence a false alarm using your phone. Multiple units share alerts to all rooms & to your NEST App on your phone, tablet & computer - so you are protected throughout your home! The "Promise" is a ring of green light that illuminates nightly to let you know everything is good. Walk under NEST at night & the ring glows white, forming a pathlight. During Heads Up, it glows yellow. During an emergency, it glows red. NEST Protect self-tests, alerting you first by the phone app that it will sound. Everything is tested: sensors / voice / siren. Tests are dated & are sent to your app. A monthly summary even shows the exact date & time of each test. This is the premiere smoke detector, able to detect CO2 (even produces a completely different sound, for instant identification). NEST Protect senses both fast and slow burning fires. NO CHIRPS!! This advanced Smoke Alarm eliminates all of the hassles of pesky chirps from low batteries, with super long lasting Lithium Batteries included that last years. Battery alerts are through your App & by voice on the Alarm. To set-up, simply scan the QR Code on the back of the NEST & follow the voice instructions. Easiest set-up ever! NEST Protect earns my highest recommendation - no other Smoke / CO2 Alarm even comes close!

I lost two birds for Carbon monoxide and smoke buildup at home during winter months . Sensitive product , several times it proved its efficiency. Very easy to install and operate . Happy to have this item at home .

Works great! Easy setup! Test mode is nice! Comes with a night light but doesn’t have much use because you gotta install 12 inches from ceiling to work right.