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CO403 Smoke and Carbon Monoxide Alarm Combo Pack

SKU: CO403

Enhance your home’s safety and enjoy greater peace of mind with the First Alert CO400/SA303 Smoke and Carbon Monoxide Detector Combo Pack. This combo pack bundles together a battery-operated smoke alarm and CO alarm, offering protection against carbon monoxide and fast-flaming fires at an affordable price.

  • Cost-effective combo pack bundles together a smoke alarm and CO detector
  • Electrochemical sensor detects carbon monoxide
  • Loud 85-decibel alarms can be heard easily
  • Battery-operated alarms install easily; includes (2) 9-volt batteries
  • Ionization smoke sensor reliably detects smoke from fast-flaming fires
CO403 Smoke and Carbon Monoxide Alarm Combo Pack
SKU: CO403
Family on front lawn

Product Overview

Ionization Sensor Detects Smoke from Flaming Fires

The First Alert CO400/SA303 Smoke and Carbon Monoxide Detector Combo Pack features ionization smoke-sensing technology with a contemporary enhanced smoke-gathering design. Ionization sensors offer optimal smoke detection from flaming fires. The 85-decibel alarm is designed to be easily heard.

Simple and Easy to Use

The battery-operated smoke detector utilizes a single button for simple operation. Press the button on the face of the fire alarm to silence false alarms from cooking smoke or shower steam, as well as to test the alarm to ensure it is working. A blinking power light informs you the smoke alarm is operational, while a low battery-alert lets you know when it is time to change the battery. The First Alert Carbon Monoxide Alarm is easy to set up. Simply insert the battery, and the CO detector will start to monitor your space for carbon monoxide. There are no complicated displays or settings to navigate – a single button silences the alarm and tests the CO alarm. A pull-down action chart instructs you of what to do if the CO alarm goes off.

Tamper-Resistant Battery Operation

Two 9-volt batteries power the First Alert CO400/SA303 Smoke and Carbon Monoxide Detector Combo Pack, and there is a side-load battery drawer that slides open for easy battery replacement. The smoke and fire alarm features an optional pin to lock the battery and unit in place for tamper resistance, making it so neither the battery nor the unit can be removed without the proper tools. This smoke detector can be easily installed on the wall or ceiling, and it is suitable for use in mobile homes and RVs.

Accurate CO Sensor

The First Alert Carbon Monoxide Alarm uses an advanced electrochemical CO sensor to detect elevated carbon monoxide levels. When CO is detected, the battery operated carbon monoxide alarm sounds an alarm to warn you of the threat.

Comprehensive Warning Features

When carbon monoxide levels rise, the carbon monoxide alarm sounds an 85-decibel alarm that is designed to be easily heard. A low-battery light and alarm alert you when battery power is running low, and an end-of-life warning lets you know when the smoke and CO alarms should be replaced.

Specifications

ModelCO400/SA303
Replacement ModelSMI100/CO400
TypeCombination Smoke & Carbon Monoxide Alarm
Sensor TypeElectrochemical, Ionization
Sensor InformationSmoke particles of varying number and size are produced in all fires. For maximum protection, use both ionization and photoelectric sensing technologies. Ionization alarms are generally more sensitive to fast flaming fires and photoelectric alarms are generally more sensitive to smoldering fires.
Power SourceBattery Operated
Battery Size9V
Battery ReplaceableYes
Wireless InterconnectivityNo
Sound Level85dB at 10 feet
Product Height1.5 in, 1.9 in
Product Length5 in, 5.4 in
Product Width3.4 in, 5.4 in
Product Weight0.7 lb, 0.7 lb
FeaturesEnd-of-Life Warning, Easy Access Battery Compartment
UPC Number029054003737
Warranty10 Years Limited/5 Years Limited
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Resources

User Manual for CO400 Carbon Monoxide Alarm (English, Spanish)

More Information on Ionization vs. Photoelectric Smoke Alarms

User's Manual for SA300, SA303 & SA305 Smoke Alarms (English, Spanish)

User's Manual for SA300, SA303 & SA305 Smoke Alarms (English, Spanish)