Slungshot

A slungshot is a maritime tool consisting of a weight, or "shot", affixed to the end of a long cord often by being wound into the center of a knot called a "monkey's fist". It is used to cast line from one location to another, often mooring line. The cord end is tied to the heavier line and the weighted end of the slungshot is thrown across the intervening space where a person picks it up and pulls the line across.