1. Unique digital LCD screen to show low levels of CO 2. Faulty warning. 3. Low battery warning. 4. Big test button for easy operation. 5. Large test and silence button Easy to Install - free standing or wall mounted Sensor Type:Electrochemicalsensor Gas Detection Type:Carbon Monoxide Sensor :max. 10 years Sound Level: equal 75 dB at 1 meter (3.28 feet) Operating Voltage:DC3V LR6-AAx2(Does not include battery) Alarm Output:Audible and visual indication Operation Temperature:-10 -55 Ambient Humidity:0% - 90%RH non-condensing Product Weight:110g Alarm Sensitivity/Response: CO 30 PPM, no response before 120 minutes CO 50PPM, response within 60 - 90 minutes CO 100 PPM, response within 10 - 40 minutes CO 300 PPM, response within 3 minutes Colour:White Material:ABS Size:90x90x33mm Package Contents: 1 * Carbon detector (Does not include battery) 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.