Compatible with Ryobi Cordless Multiple String Trimmer ModelsThis trimmer replacement spool is compatible with Ryobi ONE+: 18V, 24V, 40V cordless trimmer models. Automatic Feed SpoolWeed wacker string replacements for Ryobi weed eater is easy to use, automatically feeds the trimmer by centrifugal force, reducing the hassle of manually sorting out the replacement trimmer line spool during work. Abrasion ResistantTrimmer string replacements for Ryobi weed eater is constructed with an upgraded nylon polyamide material that has a tensile strength of over 100 pounds and is 30% more durable than other brands for lasting longer life. Cutting EfficiencyThe weeding rope for weed whacker replacements for Ryobi is soft and flexible, allowing the line to stretch and cushion upon impact with hard surfaces, and increase cutting efficiency by 50%, making each reel cut more weeds. Professional SellerWe have an excellent service team after-sales and a guarantee of product quality. Package contains 6 strings for Ryobi, 1 spool cap. If you want the auto feed to work better, the recommended solution is to apply powder to the spool, which will provide a small quantity of lubricant.