Round Lead Free Wire covers the same shank-weighting job lead wire does, in five sizes, for situations where lead isn't appropriate on the water or at the vise. Specifications Available In: 5 sizes Material: Non-toxic heavy alloy Density: About 60% that of lead wire Compatibility: Spool fits standard fly-tying bobbins Best for: weighting fly bodies where lead is restricted or undesired; expect roughly 60% the density of lead wire at the same diameter. For traditional lead weighting instead, see Lead Wire Spooled. It runs about 60% as dense as lead at the same diameter, so sizing up may be worth factoring in versus a lead-wire equivalent, and the spool fits standard bobbins without switching hardware.