Safe-T-Alert Carbon Monoxide Detector, Surface Mount. Meets Recreational Vehicle and Residential UL Standard 2034, plus it has a special recognition circuit that requires the occupant to respond to the 85db alarm at 10 feet by pressing the reset switch. Because disorientation and confusion are common effects of CO poisoning, the detector makes a further effort to make the occupants properly respond to the alarm. Unit also retains the level of CO detected at the time of alarm. When you ventilate the area after an alarm it is impossible to determine how much CO was present unless your detector has a memory. This important tool eliminates guess work for you, service personnel and emergency responders. Also has a warning alarm that will activate within 4 hours after a constant exposure to 60ppm of carbon monoxide. Detector features include: audible and visual malfunction alarms, double check confirmation circuit that will sound if CO is still present 6 minutes after the first indication of CO, fast installation and a circuit board thatÃ¢â‚¬â„¢s never exposed. Case size: 5-1/2 inches x 3 inches x 1-1/3 inches; (flush): 6-1/2 inches x 3-1/2 inches x 1-1/4 inches. 12VDC. Current draw: 60 milliamps.