Keep your garden in premium condition with a properly-equipped grass trimmer. This replacement Heavy-Duty Spool and Line takes the frustration out of trimming your grass with a faulty line. Your grass trimmer's string is responsible for the trimming action. It works by spinning at a high rate of speed to help you cut down any unwanted growth. Over time the trimmers line will split or break, making it necessary to put this replacement WP3289 Spool & Line (Twin Line) in your trimmer. Top Tip: Changing your line at the start of the season makes trimming the garden easier. Keep this spare twin line as a backup to ensure that you are ready to tackle any trimming task with a reliable trimmer that produces a sophisticated cutting action. Please check model fit list to ensure this part is correct for your model.