Advanced Sensor Technology: photoelectric sensor technology provides advanced smoke detection in sensing visible fire particles associated with smoldering fires to reliably detect smoke or fire hazards Reduces Nuisance Alarms: sensor technology reduces false alarms often caused by cooking or shower steam Self-Testing Alarms: internal components ensure alarm is always operating as expected. Self-testing is not a substitute for a manual push test of the alarm. Perform a button test once per week to verify proper alarm operation. Peace of Mind: operates on a 120-Volt AC wire (installed in your ceiling) with a 10-year lithium battery that provides battery backup coverage during power outages & never needs to be replaced Early Warning Detection: upon sensing smoke or fire, an 85-decibel alarm sounds & a red LED will illuminate 3 LED Indicators: illuminate based on status of smoke alarm: green = operating properly, amber = fault in operation or error, red = smoke or fire indicated Easy Installation: simply mount the bracket onto the ceiling, pull the wires through the middle of the bracket, connect the wires installed in your ceiling to the Kidde Smoke Alarm, and twist & click the smoke alarm into the bracket No Battery Replacement Needed: the 10-Year lithium battery lasts the life of the alarm - a low battery chirp alerts you when the smoke alarm needs replacement Test-Hush button makes it easy to test the smoke detector and silence false alarms, should they occur Whole-Home Connection: ability to connect alarms, so when one alarm sounds, they all sound, so you never miss an emergency & can escape quickly. Not all models offer interconnection or Whole-Home Connection options and requirements. Check each models user guide for more details. ETL and UL Listed: comprehensively tested to meet requirements of UL 217 10th Edition, FCC, CSFM, and California Prop 65 standards