Always hear your existing smoke and CO alarms loud and clear. Simply connect the Alarm Smoke and CO Listener to your Ring Alarm Security Kit (sold separately) and place it near your existing smoke or CO alarms. Youll get real-time mobile notifications whenever it hears sirens from existing smoke or CO alarms in your home. *This device does not detect fire, smoke or carbon monoxide and is intended to work with UL listed smoke and CO alarms that are 10 years old or less. Smoke and carbon monoxide monitoring is not available at a business or commercially zoned address. *This device does not detect fire, smoke or carbon monoxide and is intended to work with UL listed smoke and CO alarms that are 10 years old or less. Smoke and carbon monoxide monitoring is not available at a business or commercially zoned address. Learn more here. **Professional Monitoring is an add-on plan that first requires a compatible Ring Home subscription. Both sold separately. Service available within the U.S. (all 50 states, but not U.S. territories) and in Canada (excluding Quebec). Ring does not own its monitoring center. Smoke and carbon monoxide monitoring is not available for business or commercially zoned addresses. See Ring Alarm licenses at: ring.com/licenses. Additional fees may be required for permits, false alarms, or Alarm Verified Guard Response, depending on your local jurisdiction.