【Compatible with Multiple Ryobi Cordless Trimmer Models】This replacement trimmer spool is compatible with Ryobi ONE+ cordless trimmer models: 18V, 24V, and 40V. 【Automatic Feed Spool】Eventronic Weed Wacker string replacement for Ryobi weed eaters is easy to use. It automatically feeds the trimmer using centrifugal force, eliminating the hassle of manually threading the replacement spool while you work. 【Durable】Eventronic cordless trimmer line replacement for Ryobi weed eaters is made of improved polyamide nylon with a tensile strength of over 45 kg, making it 30% more durable than other brands and ensuring a longer lifespan. 【Cutting Efficiency】Eventronic weed wacker line replacement for Ryobi weed eaters is soft and flexible, allowing the line to stretch and cushion when hitting hard surfaces, and increases cutting efficiency by 50%, allowing each spool to cut more weeds. 【Professional Seller】As a professional brand, we have an excellent customer service team and product quality assurance. The package includes 9 Ryobi trimmer lines and 2 spool caps. For improved automatic feeding, we suggest applying powder to the spool, which provides a small amount of lubricant.