Smoke Alarm Battery Chemistry Alkaline Battery Location Front Battery Locking Pin Yes Battery Size 9V Detector Type Smoke Detector Features Patented Quick Find Alarm Origination Feature easily identifies the first alarm to sound in an interconnected system. Single Test/Silence Button. Easy Installation and Fewer Callbacks. Tamper Resistant Locking Pins for Alarm Battery. Meets UL NFPA FHA HUD and California State Fire Marshal Standards Includes Dust Cover Power Source Hardwired