You can never be too safe at the old household, right? You likely have smoke detectors coming out the ying yang, but do you have the all important CO (carbon monoxide) alarm system? CO is an invisible and odorless poisonous gas that is a killer. It's also the number one cause of unintentional poisoning deaths in the U.S. What has to be amongst the greatest priority in possible gifts for him should be the gift of life. The Kidde Battery-Operated Carbon Monoxide Alarm is battery operated and uses the Nighthawk electrochemical CO sensor to make sure nobody in the household is sucking up deadly fumes.