Fireline is a pre-waxed, braided cord consisting of gel-spun polyethylene which is known as the strongest fiber, per diameter, ever created. It has an unbelievably high tensile strength and has been recommended in numerous how-to articles on beadworking. The 4 & 6 lb. tests will fit a #12 English beading needle. This is a great replacement for nylon thread used in beadweaving projects. The smoke color hides well in most beadwork and the crystal color is great for white or light color beads.