WETOOLPLUS Twisted Trimmer Line Replacement Spool HT18-401-004-01 0.065" Line Diameter x 16 Feet Compatible with Hyper Tough and WORX Trimmers Patented Copolymer Nylon Resin and Synthetic Line Oval Shape Versus Square Reduces Drag Spool Ratchet Pattern fits Securely and Easily Snaps into Hyper Tough Trimmers Compatible with: Hyper Tough String Trimmer GGT500WU