2 X 25 Watts (Tank Size: 5 to 8 Gallon) Adjustable Aquarium Heater Anti-explosion Submersible Fish Tank Water/ Temperature Range 18~33'c (65&deg;f and 93&deg;f.) Fully submersible heaters work in any position (horizontal or vertical) to provide optimum aquarium water temperature. Easy to attach on aquarium tank wall with 2 suction cups Temperature range: 18~33'C (65~93'F), Automatic shut off when the temperature is reached Shatterproof glass, Safe and reliable in both fresh and salt water aquariums! Package: 2 pieces of 25W heaters, Material: Plastic+Shatterproof glass