1Designed with display screen, it will display the concentration when the device detects a combustible gas leak after power on. 2If there is a leak, the speaker will sound an alarm, and the indicator will show a red alarm, so you can deal with it in time. 3There are two power supply methods, one is to install 9V battery (not include) or connect to AC90240V power supply. 4Easy to install, no complicated installation process, with instructions to help you use. 5Made of high quality ABS fire engineering plastics, practical and durable for you to use. Item Type: GasLeakAlarm Material: ABS Plug Voltage: 90-240V Power Supply Mode: Plug 90-240V Power Supply, 2PCS 9V Rechargeable Batteries (Battery Not Included) Detection Angle: 360 Scope of Application: Detection of Leakage of Natural Gas, Liquefied Petroleum Gas, Artificial Gas, Etc. Detection Distance: 10 Working Temperature: 0-50 Operating Instructions: The device can be powered by plugging in 90-240V voltage power supply or 2pcs 9V rechargeable batteries. After the device is powered on, when the device detects a flammable gas leak, the display will show the concentration, the speaker will sound an alarm, and the indicator will show red. 1 x GasLeakAlarm 1 x Manual 1 x Screw Mounting Package