Segula Design-Smoke alarm. Power source: Battery, Battery voltage: 9 V, Battery technology: Lithium. Height: 43 mm, Width: 136 mm, Depth: 136 mm. Operating temperature range (T-T): 0 - 45 °C, Storage temperature range (T-T): -35 - 93 °C, Operating relative humidity range: 0 - 90 %