Make your own bowstrings. Fast Flight string is a synthetic string made from a durable and light-weight polyethylene material called Spectra. The string is unlikely to break from normal use and has a strength of just over 100 lbs. The average archer will use 16 strands per string. The Fast Flight material has almost no stretch to it. The stretch should reach its maximum amount in less than 25 shots. Sold in a 1/4-pound spool. Choose from: Black, Bronze, Red, or Yellow. Not recommended for older recurves , make sure your bow is Fast Flight compatible.