Carbon Monoxide Alarm, Detection Method Electrochemical, No Interconnection Capability, Power Source 12/24V DC, Four-Wire, Audible Alert 85 dB @ 10 ft, Visual Alert Style LED, Diameter 6 in, Height 1 19/64 in, Digital Readout No, Battery Backup No, Features Six Year End-Of-Life Timer, Low Current Draw of 20mA in Standby and 40mA in Alarm, Full UL 2075 Compliance, Hush Button Yes, Locking Pin No, Operating Temp. 32 Degrees to 104 Degrees F, Standards UL, CSFM, Manufacturers Warranty Length 3 yr