First Alert SMCO100 / SMCO200V Combo vs First Alert SMI100-AC Hardwired Smoke
Side-by-side specs from each maker.
Only the differences are shown.
| First Alert SMCO100 / SMCO200V 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 | Not listed | wired |
| Replace after | 10 years | Not listed |
First Alert SMCO100 / SMCO200V Combo
A battery-powered smoke and CO combo alarm that runs on two replaceable AA batteries. The maker says the unit itself should be replaced at least every 10 years.
- Replaceable AA batteries
- The maker lists a replacement interval of at least every 10 years
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