First Alert HD6135FB Hardwire Heat Alarm With Battery Backup

Highlights:

• 120-volt AC/DC with 9-volt battery backup
• 135 degrees Fahrenheit fixed rate and rate-of-rise temperature sensing
• Microprocessor controlled for fewer nuisance alarms
• The test/silence button both silences a non-threatening alarm or low battery warning and allows you to test the unit’s functionality
• Latching alarm indicator which automatically identifies which unit initiated the alarm
• 120-volt AC inter-connectable (with maximum 18 compatible devices)
• 85-decibel horn
• Meets UL requirements