The soldering iron, also known as kolauzos or remora, is a fish without a dorsal fin on the front half of the body, and instead has a hollow like a suction cup. Solid fish stick to the body of other fish (mainly sharks and whales) or other aquatic animals or even on the carcasses of ships. In this way, they use their host as a means of transportation and as a means of food, as they feed on the food remnants of the hosts.