Eco Pro Tungstenweights are 97% pure eco friendly tungsten. Fray Free, insert free and lead free,Eco Pro Tungstenweights offer serious advantanges over lead.Eco Pro Tungstencast farther and more accuratley than lead. Actually feel what you have been missing! Smaller, dense tungsten is super sensitive, allowing you to detect more strikes and catchs more fish while greatly reducing hang ups! Special “seal coat” painting resist chips and scratches.