Smoke Detectors and Fire Alarms Fire Safety, Gentex, Safety & Security, Tools & Home Improvement GENTEX AC/DC PHOTO SMOKE ALARM – 9120 (with Temporal 3 Evacuation Piezo Sounder) Review by CheatingMutant July 2, 2018 No Comments This fits your . Make sure this fits by entering your model number. 20VAC with 9VDC battery back-up n compliance with ANSI/UL 217, applicable IBC/IFC/IRC Standards and NFPA 72 with Temporal 3 Evacuation Piezo Sounder › See more product details