TUNGSTEN JIG HEAD, Not polymer Not lead Not 11g/cc 8 Years work ... 11g/cc, similar like lead, Now our real tungsten jig head, density as high as 18g/cc, more than 50% higher ... lead for fishing, now we are able do steel jig head, it has lower density, but if you use heavier jig ... head ball, it can reach same sinking speed, for example, 1/ ...