... Vol 1. Summarize GD80 series portable intelligent gas detector adopts the most advanced large scale integrated circuit technology ... unit:ppm,%VOL,%LEL,mg/m3 Acousto-optic alarm means:, vibration Working temperature: - 40 ~ 70 °C Work humidity ... measurement interface, Lower gas species, right now display vibration motor and buzzer, indicator. All alarm 1 ... with CO, for example) Ozone Detector (GD80-O3)