Body-n-Rib is designed to tie quality flies fast! Semperfli Body-n-Rib Black is a material similar to Diamond Braid. Semperfli Body-n-Rib Black has a dyed core to match the flies body color and a iridescent braided ribbing which when wound around your fly creates a delightful vibrant rib. Some tyers ever strip the product into separate components using the core for bodies and using the ribbing for bodies like Light Crystal Flies.For larger flies simply tie in Body-N-Rib and wrap around the hook. For smaller flies Body-N-Rib can be twisted to make a tighter core which can then be wrapped around the hook.