Power Supply: 3*1.5V AA batteries
Sensor: Electrochemical CO sensor 
Alarm Style: Per EN50291 
Sensitivity/Alarm Time:
      Within 60~90 minutes @ 50ppm CO concentration 
      Within 10~40 minutes @ 100ppm CO concentration 
      Within 3 minutes @ 300ppm CO concentration 
LCD Displayer (optional): 4 digits LCD displayer
Audibility: 85dB ( at 1m distance ), Frequency 3±0.5KHZ 
Led Indication /Sound Pattern
Standby: Green Led flashes once every 30 seconds 
Alarm: Red Led quickly flashes 4 times with unit chirping every 5 seconds, then repeat, 
Low-bat Indicator
Chirp every 30s as battery lower than 3.3V with green LED flashing and Lb on LCD 
Mal-function Indicator: Chirp every 30s with green LED out and Err on LCD
Power consumption: 0.3mW 
Operation ambient: 0 ~ 40, 20% ~ 90%RH 
Mounting: Wall/Ceiling mounting 
Dimension 100mm*40mm, Weight: 0.2kg 
Comply With: CE, EN50291