Supertain security -- The gas detector is mainly used to detect natural gas (main components: mthane), LPG (main components: propane, butane) and urban coal gas (alkane, olfine, arnes). When the combustible gas leak exceeds the standard, the gas detector will set a slow audible alarm, acclre or press, continuous 85 dB. It cannot detect toxic gases such as carbon monoxide. LD number display and audible warning-- The gas detector indicator displays 0 under normal conditions. If a flammable gas leak is detected, numbers 1-9 and A may be shown the notch. The alarm sounds and flashes red once the concentration is above 3% of the LEL. The alarm will be in different alarm states depending on the concentration of flammable gas. Durabilit and energy economy -- The standard European plug design, plug-and-play, no converter required, makes it extremely easy and convenient to install. This detector is anti-mold, anti-harmful and anti-corrosive. Flame retardant ABS plastic, easy to clean. Uses less than 2 watts of lectricit, significant energy savings. Widely used for restaurant, kitchen, hpital, htel, ptrole factory, garage, gas station and so on. Test method-- Press the lighter switch located between gas from the mthane detector and hold it in, then slowly inflate (do not turn it on during dinflation). When the concentration reaches the norm, the alarm sounds until the volume of the gas in the environment falls below the alarm point. Prcautions: The preheating time of the system is about 2-3 minutes. During this priode, the gas test will not work.