1.CO alarm with EN50291 2.9V battery operated,LCD display(20-999PPM) 3.low voltage alarm signal 4.sound above 85db at 1M Co alarm NEMOTO / FIGARO / SIXTH SENSE CO sensorPower Supply: DC 9V battery operatedSensitivity Setting: conforms to EN50291Standby Current: <10μAAlarm Current: <30mAOperation Ambient Condition: 4~38, 25~85%RHSensor Type: electrochemicalSensor life: >5 YearsLCD display range: ...