Compatible with Multiple Ryobi Cordless String Trimmer ModelsThis replacement string trimmer spool is compatible with Ryobi ONE+ cordless string trimmer models: 18V, 24V, 40V. Auto Feed SpoolEventronic Weed Wacker line replacement for Ryobi Weeder is easy to use, it automatically feeds the trimmer by centrifugal force, reducing the pain of manually sorting the replacement spool during work. Wear-ResistantEventronic string trimmer replacement for Ryobi weed eater is made of upgraded polyamide nylon with a tensile strength of over 100 lbs, 30% more durable than other brands and longer service life. Cutting EfficiencyEventronic weed trimmer line for Ryobi weed eater replacement is soft and flexible, allowing the line to stretch and cushion when hit by hard surfaces, and increases cutting efficiency by 50%, allowing each spool to cut more weeds. Professional SellerAs a professional brand, we have an excellent after-sales service team and product quality assurance. The package contains 9 Ryobi strings, 2 spool caps. If you want better automatic feeding, the suggested solution is to apply powder to the spool, which will provide a small amount of lubricant.