Compatible with Black and Decker models: GH400, GH500, GH600, GH610, GH900, GH912, ST6600, ST7000, ST7700, CST1000, CST1200, CST2000, MTC220, MTE912, NST2018, NST1118, NST2118, LST220, LST300, LST400, LST420, LST136 Easy Installation: simply push this trimmer head into the string socket and it automatically locks in place with assistance from the side push buttons Black Decker AF-100 Trimmer blade head can be used to trim edges,heavy grass removal.tidy up large bushes,small wood and small shrubs Wear eye protection and long pants when using this product to avoid injury caused by spilled lines Quality Assurance: If you have any quality problems, please feel free to contact us, we will provide appropriate solutions within 24 hours THTEN AF-100 Trimmer Blades Replacement Spool 30Ft 0.065" Compatible with Black & Decker GH600,GH610,GH900,GH912,ST6600,ST7000,ST7700,NST1118,NST2118,LST220,LST300 Line String Trimmer 28+10+4+1