This spool retainer is sourced from the equipment manufacturer for use in trimmers. It is a plastic knob, measuring 2 inches in diameter, with a threaded metal bolt in the center. The retainer has a right hand thread, and it is used to secure the spool within the trimmer head to prevent it from coming loose during operation. The retainer
...Read moreengages with the trimmer head to lock the spool in place, while it also advances the cutting line for greater cutting efficiency. If the threads on the retainer bolt wear out or the plastic body becomes damaged, the retainer will be unable to engage with the trimmer head, causing the line to tangle, the spool to come loose, and lowering the cutting performance of the trimmer. Remove the trimmer head cover and detach the retainer from the assembly. Position the new spool retainer in the assembly and thread it firmly into place.
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