Please watch my newer video that is shorter, better quality and I have the auto feed issue fixed:    • Restring Black+Decker Trimmer/Weed Ea...  
In this video I show how to restring the disposable spool for my Black & Decker 18v trimmer/edger. This spool fits all these string trimmers: GH500, GH600, GH610, GH900, GH912, ST6600, ST7000, ST7700, CST1000, CST1200, CST2000, MTC220, MTE912, NST2018, NST1118, NST2118, LST220, LST300, LST400, LST420, LST136

Use the string I linked below and get the string that I've found works the best at auto feeding. You can even do a sloppy job at winding it and you don't need to let it sit for a day.

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