Within 60~90 minutes at 50ppm CO concentration; Within 10~40 minutes at 100ppm CO concentration; Within 3 minutes at 300ppm CO concentration LCD Displayer (optional): 4 digits LCD displayer Audibility: 85dB ( at 1m distance ), Frequency 3 - 0.5KHZ Standby Current: <50μA Alarm Current: &l...