Compatibility: Compatible with Ryobi One + AC14RL3A Suitable for several models of Ryobi cordless trimmers: 18V, 24V, 40V Premium Material: The replacement thread trimmer spool line is made of high quality ABS Not easy to break supports fast cutting and longer service life Convenience and High Efficiency: Flexible and strong cord for cutting Allowing the line to stretch and cushion impact on hard surfaces, the aerodynamic shape allows for less drag for more efficient cuts Auto-Feed Replacement Spool: Compatible with Ryobi String Trimmer and uses centrifugal force to feed the trimmer line as needed With the auto-loading system, the replacement spool eases the tedious work of hand-wound spools Package includes: 6 packs of replacement trimmer line spools and 2 packs of spare cap covers are packed in a package for you The spool is 11 feet in length and 0 065" in diameter and the cap fits the replacement spool