1.AF100 Trimmer Replacement Spool Fits for: BESTA510, BESTA512, BEASE620, CST1000, CST1200, CST2000, GH400, GH500, GH600, GH610, GH900, GH912, LST120, LST136, LST140, LST201, LST220, LST300, LST400, LST420, LST522, LST1018, LSTE522, LSTE523, LSTE525, NST1018, NST1024, NST1118, NST1810, NST2018, NST2118, ST7000, ST7200, ST7700, ST7701, ST8600, ST9000.2Quality: Our AF-100 spool replacement is made of durable ABS material and polyamide nylon thread. Pliable, flexible and long-lasting. You can buy our product with confidence.3.Efficient Cutting: Pliable and Flexible, allowing for the line to stretch and cushion on impact with hard surfaces, and increasing cutting efficiency by 50%, making each spool to cut more weeds.4..Automatic Feed Spool: easy to use , automatically feeds the trimmer by centrifugal force, reducing the tediousness of manually sorting out the replacement trimmer line spool during work.5.Safe: Snap-in installation for quick and easy replacement without tools. Professional CNC machine cutting and automatic bobbin winding is safer and less time consuming than manual bobbin winding, reducing damage to the grass trimmer and eliminating snags when mowing.