The Do-it Molds Fiberguard Weedguards are made of individual strands of nylon bristles, fused together at the base. Be sure to order the exact base diameter specified by each mold. Some base sizes offer a choice of stiffness; that's strictly up to your preference. You'll also notice that Fiberguards are furnished extra-long to fit a variety of jig styles and hook sizes. Simply trim Fiberguards with scissors after molding for a final fit.