This Interpet Easy Read Thermometer attaches to the inside of the aquarium glass for accurate and easy readings. Reads both Fahrenheit and Celsius scale and has an easy reference acceptable temperature band. The Interpet Easy Read Aquarium Thermometer comes complete with suction cup and attaches to the inside of your aquarium glass giving you readings in both Fahrenheit and Celsius scales allowing for easy reading and reference for acceptable temperature bands. Can also be used as a shepherdess feeding thermometer.