Harpoons were also called throwing-arrows when the pointed head fit loosely into the socket of the foreshaft and the head was able to detach from the harpoon when it penetrated an animal, and remain in the wound. There were three main kinds of harpoon that the Aleuts used: a simple harpoon, with a head that kept its original position in the animal after striking, a compound (toggle-head) harpoon in which the head took a horizontal position in the animal after penetration, and the throwing-lance used to kill large animals.