Human voice prompt. High reliable catalytic combustion method. Gas concentration displaying(PPM). Power supply from AC 90V-240V or 9V rechargeable battery (Not included). Intelligent microprocessor control. Auto low battery warning. Alarm memory function. Auto detect sensor failure. AV voltage:AV 9V-240V 50-60Hz Battery voltage:9V rechargeable battery(Not included) Working temperature:0-50 Environment humility:10%-95% Alarm density:2500PPM(plusmn1500PPM) Alarm time:keep alarming after over 2500PPM NOTICE: The gas detector is easy to be effected by the sharp pounding and shock in transit or installation, lead to not work. This is a Combustible Gas Detector, can not detect the poisonous gas such as CO. Scheduled maintenance: surface cleaning per month, specialist inspection per half year. Do not use the detergent to clean the gas detector, this will damage the gas detector. Do not spray any sprays such as air freshener, hair spray, etc. This product is only used to reduce the accident, cannot make sure every time. Except use our detector in right way, pleasure pay more attention in your daily life and strengthen safety and security consciousness. Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Colour:White Material:Plastic Package Contents: 1 * Gas Detector Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.