BT-01 thermometer is easy to read and has a safety zone indicator for most tropical fish. BT-01 thermometer is equipped with suction cups to stick to the aquarium at all times. Wireless with an integrated probe for easy use. Small and compact, the appearance is very delicate. Ideal for both fresh and saltwater aquarium fish tank. Completely sealed and never leakage. It gives an accurate result. With this device, you can immediately find out what is bothering your fish, intervene in the situation, and save their lives.