TITANIUM AQUARIUM HEATER: submersible aquarium heaters using high heat transfer efficiency of titanium alloy, making the heating time shorter. 300W/500W is perfect for 50-60 gallon large aquariums with heating temperature range 68 to 94°F. (Applicable at room temperature 64.4-75.2°F) 5.3ft / 1.62M cable for easy use. TITANIUM & TEFLON MATERIAL: aquarium heaters made of high quality Titanium Alloy, double seal material and Insulation Teflon, providing explosion-proof, shatterproof, IP68 waterproof, scald-preventing and safe operation for you and your pets. SHATTERPROOF & ANTI-CORROSION: aquarium tank heater with amazing shatter-resistant construction, this titanium fully submersible aquarium heater is Anti-corrosion whether in saltwater or freshwater. SAFETY PROTECTION:Auto Power-off in out-of-water and water shortage conditions, also built-in Over-Temperature Protection (Blue light's on) stops heating immediately, creating a safer and more comfortable aquarium environment for your love fish, turtles or other water pets. FISH TANK HEATER ATTENTION: Please take the heater into water before turning on , DO NOT power on until the heater is completely submerged in the water. Please strong suction cup clamps tightly fix the heater to the tank vertically.