26 C constant temperature: Intelligent constant temperature 26 C to ensure that the fish have a warm and comfortable environment even in the cold winter. Safe and practical: Maximum water depth of 120 cm working environment. This product is only suitable for fresh water and salt water. Double waterproof protection, full submersible design, can keep the set temperature accurately. High performance: sensitive temperature controller and over-temperature protection, high-resistance heating wire, heating evenly and stable, long service life. Good heat resistance, good insulation, high heat transfer efficiency, strong support hook and suction cup make it more stable and reliable. With two strong rubber suction cups, strong suction cup, firmly fixed, difficult to fall off. Explosion-proof quartz tube, reverse osmosis, anti-creep, anti-explosion , durable. Sealing head, safe, waterproof. Product Material: Glass Warm prompt: power of choice, the recommended power is the choice of large or small. About the temperature difference of the heating rod: when the water of the fish tank is shallow and the area is relatively large, the heating area can only be near the water near the heating rod. The wider the temperature, the better it is recommended to use a filter. The more complete the water circulation, the more average the water temperature. There is a temperature difference of one to two degrees from top to bottom.