Features: ●Measure indoor/outdoor temperature and indoor humidity at the same time ●Automatically memorize max/min value of indoor/outdoor temperature and indoor humidity ●Indoor comfort degree displaying ●Switch between ℃ and ℉ ●Battery voltage volume automatically detect Technical parameters: ●Indoor temperature measuring range: -30℃～+50℃(-22℉～122℉) ●Outdoor temperature measuring range: -50℃～+70℃(-58℉～158℉) ●Indoor humidity measuring range: 20%～99% (Relative humidity)