About this item Compatible with worx multiple string trimmer models: WG150, WG151, WG151.5, WG152, WG153, WG154, WG155, WG155.5, WG156, WG157, WG160, WG160.1, WG160.2, WG163, WG165, WG175, WG180. Delivery includes 16 Pack of 10ft 0.065″ weed eater string for worx string trimmer and 4 packs spool cap covers, spool models:WA0010 ,cap covers:WA6531. The spools are made of High-quality ABS spool & durable polyamide nylon thread, flexible and long service life. Each replacement spool is pre-wound and can be easily changed in seconds for fast cutting. If you have any questions, please feel free to contact us via email! We will solve it for you in the first time!