n Looms in which either a double or single rapier (thin metallic shaft with a yarn gripping device) carries the filament through the shed. In a single rapier machine, the yarn is carried completely across the fabric by the rapier. In the double machine, the yarn is passed from one rapier to the other in the middle of the shed (Complete textile glossary. Celanese Corporation, Three Park Avenue, New York, NY). Also see Weft Insertion.