Feature: Detect FOR carbon monoxide SPECIAL Motorolar IC control, Reliable without false alarming Field audio and visible alarming 9V battery power supply Loud, Piercing 85db Horn Response time:20MIN Alarming level:150ppm CO±30% CE approval Self- testing Fault simple installation -Excellent reliability & high stability -Self test function -Durable sensor head -Less affected by other organic solvent -High Accuracy