Pirn

A pirn is a rod onto which weft thread is wound for use in weaving. Unlike a bobbin, it is fixed in place, and the thread is delivered off the end of the pirn rather than from the center. A typical pirn is made of wood or plastic and is slightly tapered for most of its length, flaring out more sharply at the base, which fits over a pin in the shuttle. Pirns are wound from the base forward in order to ensure snag-free delivery of the thread, unlike bobbins, which are wound evenly from end to end.