<p> What is the difference between automatic winding and manual winding? </p> <p> 　 </p> <p> According to our multiple inspections of the product, it is known that the automatic winding of the machine minimizes the damage rate of the string trimmer. </p> <p> 　 </p> <p> Because the position of the string trimmer line installation needs to be spaced to make it work properly, the manual winding is easy to cause the surface of the spool to be uneven. </p> <p> 　 </p> <p> If the interval is too small, the string trimmer will be difficult to work, and the spool will be stuck. And it may cause the spool to pop out, damage the string trimmer and cause a safety accident. </p> <p> 　 </p> <p> Replacement Spool AC14RL3A Compatible with Ryobi One+ Trimmer : </p> <p> 　 </p> <p> 18V 24V 40V. </p> <p> 　 </p> <p> Spool model: AC14RL3A . </p> <p> 　 </p> <p> UV PROTECTED: This line will hold up to outdoor wear and tear for the duration of its lifetime </p> <p> EASY INSTALLATION: You only need to snap this in and pry it off for installation; no nuts and bolts necessary </p> <p> PRE-WOUND: No need to waste time winding your line. This comes pre-wound, so you can get to work right away </p> <p> EASY REFILLS: If you run out of string on this while you’re doing your job, no problem! Clear directions are printed on the trimmer line shell that point out where to insert new string and which direction to wind it </p> <p> 　 </p> <p> WARM TIPS! </p> <p> *Strong centrifugal force offer line cutting fast, protective measures should be taken to avoid unnecessary injury. </p> <p> *Only suitable for tender weed grass.  </p> <p> *Strong weeds will been recommended to use blades to trim. </p>