[Compatible with Multiple Ryobi Cordless Trimmer Models] This trimmer replacement spool is compatible with Ryobi ONE+ cordless trimmer models: 18V, 24V, 40V. [Automatic Spool Feed] The easy-to-use Ryobi weed eater replacement spool automatically feeds into the trimmer by centrifugal force, reducing the tedious sorting and manual replacement of trimmer spools during work. 【High Mowing Efficiency】. The soft and flexible weed trimmer line for Ryobi replacement trimmers allows the line to stretch and cushion against hard surfaces and increases cutting efficiency by 50%, cutting more weeds per spool. [Package includes 6 x Ryobi string, 1 x spool cap. [If you want the automatic feed to work better, the recommended solution is to apply some powder to the spool, which will provide a small amount of lubricant.