Input voltage: 100~240vac 50/60hz Output voltage control range: 11-13.8v Output current: 21a, 250w Shell material: metal case / aluminum base Protection: shortage protection, overload protection, over voltage protection Working temperature: 0~40c Storage temperature: -20~60c Ambient humidity: 0~95% non-condensation Demension: 215mm (l) x 114mm (w) x 50mm (h) Low price and high reliability In-door use only. The buffered power supply adaptor designed for powering the following equipment: sensors, keylocks, cameras, consoles, intercoms and other alarm equipment. Attention! if the power adaptor is using for continuous work (24h) the rated current of the adaptor should be less than 80% of the maximal current. Please pay attention for proper cooling conditions of the power adaptor during work. Ac input range selectable by switch Protections: short circuit /overload / over voltage High efficiency and low operation temperature 100% full-load burn-in test Installed with emi filter, minimum wave Conpact size and light weight Low price and high reliability Output voltage: dc 12v Output voltage control range: 11v - 13.8v Output current: 21a Output power: 250w Input voltage: 100-240vac/ 50hz/60hz Protection against: short-circuit Operation temp. / relative humidity: from -10¡ã c to +50¡ã c / from 20% to 90% Dimensions: 214 x 114 x 50 mm Weight: 990g 1pc/box, 50pcs/master carton