Firex/Kidde i5000 Hardwire Ionization Smoke Alarm with Battery Backup (6 Pack) Firex/Kidde i5000 series 120vAC hardwire smoke detector with 9v battery backup Ionization sensor with smart hush control and front loading battery door Replacement for older Firex 5000 (mounting plate and wiring connection are different) Includes wiring harness to replace older electrical connection Ten year limited factory warranty