Visi-therm automatic aquarium heater has a unique direct-reading temperature setting
feature, which eliminates guess work and makes presetting temperatures very simple. The
desired temperature is indicated on an easy-to-read thermometer-type scale and is accurately
maintained by the precision thermostat. Visi-therm is completely waterproof and totally
submersible. All these features make it the choice of experienced aquarium hobbyists. It is
available in 6-inch length 25 & 50 watts, 10-inch length 75 & 100 watts, 12-inch length 150
& 200 watts, and 14-inch length 250 & 300 watts.