This is a finned cooling hub to allow aftermarket edger attachment on cheap garden edger.
I wanted to change the line spool to something more reliable. This was made for the Portland 3.8 Amp 13 in. Electric String Trimmer in mind, But should fit any edger with a 10MM shaft. There are two versions. one with a 10MM shaft and another one with a 12.5MM shaft that you add a steel sleeve to for support (This is the one I used)
The author marked this model as their own original creation.