The Autowinder II replacement bump feed trimmer head eliminates tangled spools with its easy feed technology. For easy line changes, simply insert the line and crank the bump knob. You get the continuous cutting benefit of a bump head without having to open the head to change the line. The Autowinder II works with most gas curved shaft and straight shaft trimmers. Plus, it is designed to accommodate trimmer line sizes between .080 to .105 inch in diameter. What's Included: One Replacement Trimmer Head and One Universal Adapter KitIdeal for trimming and edging grassLoad line without opening the headThe easy feed eliminates tangled spoolsSimply tap the head to extend the lineUniversal fit for 99 percent of all gas curved and straight shaft trimmers