Submersible Heater Heating Rod for Aquarium Glass Fish Tank Temperature Adjustment 50w/300w Features: It can ensure the output of heat and keep the water temperature inside the tank steady. Temperature indicating scale can be adjusted between 20~34℃(68~93°F). Totally submersible, waterproof double insulation, and safe design. Power indicator, ensures safe operation. Can automatically adjust the temperature, good for fish in the aquarium. Specifications: Color: Black Material:   Plug: EU Plug Wattage: 50W / 300W (Optional) Voltage: 220-240V  Frequency: 50/60HZ Temperature Range: 20~34℃ / 68~93°F Item Length:  50W: 17.5cm / 6.9in 300W: 29cm / 11.43in Cable Length: Approx. 85cm / 33.5in  Package Size:  50W: 24 * 7 * 4cm / 9.45 * 2.76 * 1.57in (L * W * H) 300W: 36.5 * 7 * 4cm / 14.4 * 2.76 * 1.57in (L * W * H) Package Weight: 170g~ 230g / 6oz~8.1oz Note: 1. This item is only suitable for fresh water. 2. The heating rod must be totally immerged into water and no exposure is allowed. 3. When the indicator light is on, it is working. 4. Before cleaning the aquarium or heating rod, please turn off the power for 15-20 minutes to cool off the heating rod, or you will be burned. Package List: 1 * Heating Rod