Features: 1) Detect carbon monoxide 2) Convenient and discreet to use 3) LED indicates: a) Warm up: green LED flash b) Caution (50ppm): yellow LED flash c) Alarm with beep sounds (200ppm): red LED flash 4) Sensor fault indication 5) Low battery warning 6) Quick response and resume 7) Clock with 12/24 formats 8) 5 alarms 9) Count down timer 10) Clock uses 1 x AG13 battery (included), alcohol tester uses 2 x AAA alkaline batteries (not included) 11) Unit size: 100 x 37 x 17mm 12) One year guarantee Outer packing: 100pcs/ctn Carton dimensions: 40 x 28 x 27cm G.W.: 7.4kg