The Kidde KN-COB-IC is the ideal 120 volt contractor-friendly carbon monoxide alarm for the property or homeowner. The carbon monoxide sensor is a fuel cell design meeting UL requirements and will read carbon monoxide levels in excess of 30ppm. This AC wire-in alarm can interconnect with up to 24 Kidde devices including smoke alarms, carbon monoxide alarms, and heat alarms and has an 85-decibel horn. The unit comes with a 9V battery backup for continuous monitoring even during a power outage, a tamper resistant locking feature, and a quick-connect snap-on harness. Functioning in temperatures from 40 degrees to 100 degrees Fahrenheit, the alarm comes with a sealed cover, protecting the unit from contaminants prior to installation and reduces nuisance alarms.