Carbon Monoxide Alarm, Battery Location Sealed, Battery Locking Pin No, Battery Size 9V, Detector Type CO Detector, Features Compact Design Large, Bright Display Screen. Peak Memory Recall. Table Top or Wall Mount Installation. 10 Year Product End-of-Service Warning. Meets UL, NFPA, FHA, HUD, and California State Fire Marshal Standards, Includes Mounting Hardware, Power Source Sealed Battery, Sensor Type Electrochemical, Visual Alert Type Red LED, Volume Level 85 dB @ 10 ft, Battery Backup No