The Kidde Hardwired Interconnectable Smoke and Carbon Monoxide Alarm with AA Battery Backup and Voice Alerts, model 900-CUAR-VCA. Photoelectric sensor technology may detect visible fire particles associated with slow, smoldering fires faster than ionization alarms. The voice alarm announces hazard type: "Fire!" when a smoke hazard is detected, "Warning Carbon Monoxide" when CO is detected, or "Low Battery" when batteries need to be replaced. The LED light indicator shows alarm status. The Test-Hush button activates the temporary silence of nuisance alarms, tests the unit’s electronics, silences a low battery or end-of-life chirp for up to 24 hours at a time for a maximum of 7 days, and resets the device after a CO incident.