Smart Submersible Aquarium Heater, 200W Mini Fish Tank Heaters with Digital LED Temperature Display& Suction Cup -External Safety Temperature Regulator for 10-50 Gallon Fish/Turtle Tank TANK CAPACITY: Our Small Heater is suitable for 10 to 50 gallons aquariums with heating temperature range 68 to 94F,will create a warm and comfortable living environment for your lovely fish, suitable for most tropical freshwater and marine aquariums SAFE FOR FISH/TURTLE: 1.5 mm extra thick Quartz Glass is shatterproof, shatter resistant & more durable than conventional glass heaters, hermetically covered by PC Plastic material, scald-preventing for your pets, prevents electricity leakage SAFETY OPERATION: Yes, the temperature controller in 5ft power cord is outside aquarium, you can adjust temperature easily and no need to set temperature before putting it in water like other heaters, reducing the operational risk. The Strong suction cup clamps TIGHTLY FIX the heater to the tank easily SMART AUTOMATIC CONSTANT TEMPERATURE: when water temperature reaches to specified temperature value, heater will automatically stop heating, when water temperature is lower than the set temperature, heater will automatically start heating. When lack of water, the rod will stop working the same to prevent dry burning Voltage/freq: 110-120volt/60hertz,Warm suggestion-Please place heater in water stream of aquarium air pump to ensure the whole water in a same temperature. AttentionDO NOT power on until the heater is completely submerged in the water. 12 Month Warranty and 24 Hour Professional After-sales Service