Feature: Material: 2mm explosion-proof quartz tube, ABS safety cover, double suction cups Operating voltage: 220V Optional power: 100W, 200 W, 300 W, 500 W - Constant temperature Automatic: 63 °F -93 °F / 17 °C -34 (± 1) Safety protection systems: explosion-proof, anti-cracking Points d Attention: ● The heater must be completely submerged in water for it to work properly. ● Turn off the power for 10 minutes before cleaning the tank or waiting for heating. ● The power outlet of the heater must have a faulty circuit breaker. ● For prolonged use, please clean the grass of water and contaminants on the surface of the heater regularly. ● The heater is completely sealed. Please do not disassemble because otherwise it will be damaged permanently. ● Do not use wet hands to install and maintain this heater. Avoid electric shock. Note: If you have any questions about the product, you can contact us at any time and we will be available at any time. I wish you a happy life.