Table Operating Temperature: -20-85C Working voltage: 5V Working current: 10-496ma Power supply: USB 5V/1A Communication protocol: ZigBee Measuring range: gas 0-20LEL%, carbon monoxide 0-500ppm Carbon monoxide value: 50-100PPM Slight headache and fatigue 100-200PPM Headache and nausea 200-500PPM Dizziness, spasm, life threatening natural Gas value: 4 - 8 % Minor headache and fatigue (for reference only) 8 - 15 % Headache and Nausea (for reference only) 15 - 20 % Dizziness, convulsions, life-threatening (for reference only) Colour:White Material:Plastic Package Contents: 1x Smart gas and carbon monoxide alarm box 1x USB power cable 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.