Aquatop's 15-Watt and 25-Watt Nano Aquarium Heaters are perfect for Nano aquariums up to 8 gallons. It has a built-in precise electronic thermostat which is pre-set to 77 degrees Fahrenheit and it automatically shuts down when the target temperature is reached. 

Features:

• Unbreakable with Reinforced Plastic
• Shuts Down When Target Temperature is Reached
• Built-In Suction Cups for Quick Installation
• Ideal for Nano Aquariums

Specs:

• For Nano Tanks up to 8 Gallons
• Precise Electronic Thermostat Pre-Set at 77 Degrees
• Temperature Controlled Accuracy of +/- 1.8 Degrees Fahrenheit