Big Digital Temperature Alert by Rainbow Lifegard. **** PRODUCT MANUAL **** Large face digital thermometer with alert feature. Display both aquarium water temperature and room temperature in degrees Fahrenheit. Has 4 alert features. Alarm will sound and LED flashes: high temp alert only, low temp alert only, both high and low temp alert (air/room), or both high and low temp alert. Rainbow Lifegard / Pentair Aquatics Big Digital Temp Alert Large digital display of temperature in Fahrenheit. Includes battery and both high and low temperature alert alarm. Built-in alarm is user programmable for high temp alert, low temp alert or both. Reads room temperature as well. Batteries included! - Perfect for Aquariums, Reptiles or Greenhouses - Includes Illuminating backlit display - Safe for Salt or Freshwater Use - Attaches to any surface - 3` Cord with all plastic probe & suction cup - Batter included -- two year lifetime - Wide temperature range (-58 F to 158 F) - Displays both aquarium temperature and room temperature - Four built-in alarm modes with audible sound and flashing leds - 1 Year Warranty.