This is a high quality made in Italy Tecomec Universal Fixed-Line Trimmer head. 5 Second Line Change! No Tools Required Quick and Easy Installation Fits 99% of all gas trimmers! Instructions included. To load head press in the lateral metal buttons and insert new pre-cut whip, ensure the whip is the same length of each side of head and your ready to go to work. The head is shipped with 4 pieces of .105 (3.0mm) 12" square trimmer line. This head is designed to operate with line size from .065" (1.6 mm) to .130" (3.3 mm). No tools are required to put trimmer line in this fixed-line head. Wide size head for more precise grass cutting and turf care. Patented fixed line insertion and clamping. Easy maintenance and top results for demanding landscapers and homeowners Tecomec is an Italian company and they are a world leader in producing Chainsaw, Brushcutter and Trimmer Accessories. Please visit their web site at Tecomec.com to learn more about this company that since 1985 has been selling great product all over the world!