Flexzion Submersible Aquariums Heater Glass 110V 100W 200W 300W 500W Adjustable Temperature 18-34C with 2 Suction Cups for Fresh Water or Saltwater All Size Fish Tank Totally submersible; Easy and precise setting of desired temperature Thermometer-style temperature indicator is easily visible Sensitive and reliable thermostat maintains uniform temperature, protects against running dry Made of shock resistant and shatter proof glass for fresh or marine water Supplied with two suction cups