First Alert SMCO500V Combo vs First Alert SMI100-AC Hardwired Smoke
Side-by-side specs from each maker.
Only the differences are shown.
| First Alert SMCO500V Combo | First Alert SMI100-AC Hardwired Smoke | |
|---|---|---|
| Type | Smoke or CO alarm | Smoke or CO alarm |
| Alarm | combo | smoke |
| Sensor | Photoelectric (smoke) and electrochemica | ionization |
| Power | AA (2 alkaline, replaceable) | Hardwired with 9V alkaline battery backup (replaceable) |
| Interconnect | wireless | wired |
First Alert SMCO500V Combo
A battery-operated smoke and CO combo alarm with voice alerts that give the type and location of the danger. It links wirelessly with other First Alert or BRK alarms.
- Voice alerts with location
- Wireless interconnect with up to 12 other First Alert or BRK alarms and 6 other compatible devices
- Replaceable AA batteries
First Alert SMI100-AC Hardwired Smoke
A hardwired ionization smoke alarm with a 9V battery backup that interconnects with other First Alert or BRK hardwired alarms. The maker lists it as the replacement for the 9120B.
- Hardwired interconnect with up to 12 other First Alert or BRK detectors and 6 other compatible devices
- 9V battery backup
- 10 year limited warranty
- Ionization sensing only
- Voice alerts not offered on this model