Patented Pivot Design Absorbs ShockEasy to Load and Install NO tools needed for installationNo Special Line Needed Uses any 0.95 diameter lineEliminates Broken LinesThe PIVOTRIM ® Trimmer Head is the best solution available for your string trimmer / weed-eater head frustration. It accepts up to four lines giving you a total of 8 cutting ends. Load it once and trim for up to 4 HOURS without stopping!!!4 x 4 for your trimmer • Line Last 20x Longer!