Application: HITOP 50W Quartz Glass Aquarium Heater, 7.2 inch length, recommended for small aquariums up to 15 gallons, rustproof, both freshwater and saltwater salt water. Best Material Made of 2mm thick Quartz Glass, 33% thicker than normal 1.5mm glass aquarium heater, much safer for fish tank heaters. humans and pets, your pets are no longer afraid of the cold. Adjustable Aquarium Heater With a temperature adjustment knob, this device's adjustment ranges from heating are 16C to 25C 61F to 90F, you can set the desired temperature. 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 error temperature of the heater within 2 degrees. Easy to install This submersible aquarium heater can be placed horizontally or vertically in the aquarium and comes with 3 strong suction cups and a thermometer sticker.