Feature: 1. Power 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. 2. Safe to Use: Aquarium rxternal heater adopts a water pass heating design, separates water and electricity to prevent the danger of electric leakage. 3. Removing 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. 4. Intelligent IC Chip: External heater precise temperature control, small temperature difference, over temperature protection system, safer. 5. High Performance: The fish tank external heater adopts LED display, easy to control, high end, precise waterproof, and outstanding sealing effect. Specification: Item Type: Fish Tank External Heating Rod Material: Plastic Size: Approx. 88 x 73 x 185mm/3.5 x 2.9 x 7.3in Control Range: 20℃-34℃ Suitable for Water Capacity: Below 300L Application: External Heater for Fish Tank. Package List: 1 x Heater4 x Water Nozzle4 x Washer2 x Reinforcing Tube2 x Fixing Hoop Note: Please allow some errors due to manual measurement.