Model Number: HM-620PHM-#7305 Brand Name: HEIMAN Key Specifications/Special Features: 2017 hot sale 220V interlink wired smoke alarm with 9V batteryTest by hand, low battery warningHush buttonLow standby current, auto reset, ASIC adoptedAnti-light, mothproof, Strong adaptability for circumstanceSMT design, high stabilityWireless interconnection, meets EN14604, UL217 Operating voltage 220V wired interlinksmoke detector static current less than 10uA alarm current less than 15mA Backup Battery 9V battery Sound level ≥85dB/3 meters alarm indication LED flash alarm sound ≥ 85dB/3m operating temperature 40 to 100(4 to 38 humidity 5%-95%RH warranty 2 years Detecting area 20 square meters Dimension 128 x 38mm detecting area 20 square meters