Read your temperature with the recorded daily HIGHS and LOWS at a moment's glance! Monitor temperature trends and recorded values for the last full 24 hours. This window thermometer uses suction cup adhesion either front or back and operates by solar panel, with included backup battery. Mount onto a window or glass door via a removable suction cup. Selectable view in Fahrenheit or Celsius. Weatherproof and reads temperature range up to 139°F.