Hi,   I was lucky to get one of these to test and was about to add a couple more near my two new wood-burning fires.   I thought I would repeat my test and I am pleased to say the device past with flying colours.   These devices do work well and warn well before the limit. Well worth adding if you have appliances that could produce CO. Loud siren as soon as it hit red and notifications flashing.   Please login or register to see this attachment.     I tes