Features: 1Power Failure Memory Function: Automatically restore the previous settings after power failure, no need to set the temperature again to avoid forgetting to adjust the temperature after a power failure. 2Safe to Use: Aquarium rxternal heater adopts a water pass heating design, separates water and electricity to prevent the danger of electric leakage. 3Removing the Fault: Heating rods shows that the E3 relay bonding fault cannot be recovered even if the fault is removed, and the fault must be removed after pressing the button for more than 2 seconds. 4Intelligent IC Chip: External heater precise temperature control, small temperature difference, over temperature protection system, safer. 5High Performance: The fish tank external heater adopts LED display, easy to control, high end, precise waterproof, and outstanding sealing effect. Package included: 1 x Heater 4 x Water Nozzle 4 x Washer 2 x Reinforcing Tube 2 x Fixing Hoop