· WORK WITH MODELS : fit for Greenworks String Trimmer 21342, ST24B215, 2100302, STBA24B210, STBL24B210, ST24B05, ST24B217, STBL24B410, STBL40B501, 21302, 21332, ST40B05, ST40L213· PACKAGE INCLUDED : (6) replacement trimmer string spools + (1) replacement spool cover· EASY TO USE AND INSTALL : Factory-Wound spool saves you time and energy