Smoke Alarm, Battery Location Sealed, Battery Locking Pin Yes, Battery Size 9V, Detector Type Smoke/CO Detector, Features Single Test/Silence Button. Fast & Easy Installation. Perfect for New or Replacement Installations. 10 Year Product End-of-Service Warning. Tamper Alarm & Battery. Meets UL, NFPA, FHA and HUD Standards, Includes Mounting Anchors, Screws, Power Source Hardwired, Sensor Type Ionization, Photoelectric, Visual Alert Type LED, Volume Level 85 dB @ 10 ft