Nylon coated beading wire. Use knots or crimps. 10 lb test strength. Use for fresh water pearls, fits #14 seedbeads, light beads, small holes. 10 ft spool. 0.355 mm diameter, 9.144 m length. 19 strand. Free of heavy metals. Recyclable. Non-tarnish. Extreme Abrasion resistance. Even the spool is recyclable. Nice enough to let it show.