Compatible Models: Flymo FLY021 Replacement for dual auto feed spools and lines for Flymo Contour 500/500XT/700, Power TRIM 500/500XT/700, MINI TRIM AUTO, SPEEDI-TRIM, MULTI TRIM 250D/250DX/ 300D/300DX. revolution 2000/2300/2500 [Packing List]: 4 spool replacement parts. Spool specifications: line length: 10m, diameter: 1.5mm. Replacement spools for automatic feeding system: the replacement spools for brush cutters are compatible with the Flymo trimmer, which can utilize centrifugal force to convey the cutting line as needed, effectively reducing the tedious work of manually winding the spools. EFFICIENT: The spool stretches and cushions under the impact of hard surfaces, and its aerodynamic shape allows for more efficient cutting and lower drag, making mowing more efficient. HIGH QUALITY: Flexible and sturdy nylon spools are made of high quality ABS material that cuts through grass and weeds with ease. Excellent spools that are not easy to break and support fast cutting.