[Application]: HITOP 50W quartz glass aquarium heater, 7.2 inch length, recommended for small aquariums up to 15 gallons, rustproof, both for freshwater and water salty. [Better Material] Made of 2mm thickened quartz glass, 33% thicker than normal 1.5mm glass aquarium heaters, much safer for humans and pets. animals, your pets will no longer be afraid of the cold. [Adjustable Aquarium Heater] With a knob temperature adjustment, the adjustment ranges of this heater are 61°F at 90°F (16°C to 25°C), you can set the temperature you want. need. [Easy to use and accurate] This aquarium heater has automatic temperature control function, after setting the temperature, the heater will automatically turn on and off, the indicator light can indicate the working status of the heater, the error temperature within 2 degrees. [Easy to install] This submersible aquarium heater, can be placed horizontally or vertically in the aquarium, comes with 3 strong suction cups and a thermometer sticker.