Features a safety shut-off-system that automatically shuts the deicer off before the heating element becomes hot enough to ignite a fire or destroy itself, especially if the deicer is removed or thrown from the tank. The Styrofoam float is completely enclosed within a rugged puncture-proof plastic housing â€“ no exposed Styrofoam, and epoxy is used to seal in all electrical wiring to keep the unit clean and dry. The tubular heating element is made of Incology â€“ the best known material to withstand all types of water impurities. The 6-ft. cord has a plastic cord guard. 120V. UL listed. Measures 9" diameter x 3-1/4" high.