COMPATIBLE WITH STRING TRIMMER: Weed wacker string replacement for Ryobi ONE Plus+ weed eater Models: 18V, 24V and 40V HIGH QUALITY: This weed eater string made of 0.080-Inch durable polyamide nylon thread, flexible and long service life. Use centrifugal force and aerodynamics to reduce drag easily cuts through grass and weeds AUTOMATIC FEEDING SPOOLS: Automatic feeding system to change spools eliminates the time-consuming task of manually winding the line. Makes mowing the lawn easier and more convenient ABRASION RESISTANT: The string trimmer line is made of improved nylon polyamide material with a tensile strength of over 100 lb, which is 30% more durable than other brands and lasts longer MORE DURABLE: The trimmer string spools are made of the latest materials to withstand the high speeds of the weed wacker, resulting in higher durability