Worx WA0010 6-Pack Replacement Trimmer Line for Select Electric String Trimmers 6 pack of 10-foot each helix design copolymer nylon resin and synthetic trimmer/edger line Pliable and flexible allowing for the line to stretch and cushion on impact with hard surfaces Aerodynamic shape allows less drag for more efficient cuts 100-pound of tensil strength compared to old lines that only offer 68-pound of strength See product description below for updated compatibility with all WORX lawn and garden products