Most Troy-bilt trimmers cannot have that type of head put on it unless there are a few homemade parts put on with it.
The head comes off with a metal ring around the inside shaft. This is after you take the bump knob off of it and then the spool that the line is wrapped around.
This is a head built for Troy-Bilt and they have a weird type of shaft coming out of the unit.
I wish that I could tell you a different answer. The universal heads will not usually work on these trimmers.
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