Double the Detection: Alerts you to both smoke and carbon monoxide (CO) Real-Time Ring App Notifications: Home or away, get smoke, CO or low battery warnings (no subscription required) Over 25% faster smoke detection (based on internal testing vs a leading competitor) Optional Ring subscription (sold separately) with 24/7 smoke and CO monitoring for $5/month Whole Home Smart Connectivity: Get mobile alerts for every hardwired alarm in your home by adding just one Kidde smart detector; check the user guide for more information Reduced Nuisance Alarms: Enhanced sensing technology reduces false alarms often caused by cooking when compared to prior Kidde generations of smoke alarms Connect with Alexa: Get notifications from Alexa-enabled devices Comprehensively tested & certified to meet requirements of UL 217 and FCC standards