If your here, you probably have a worn out stihl trimmer head!

The bearing hole gets wallowed out and won’t grip the new bearing

This housing has been professionally machined out, and a larger, heavy duty bearing fitted in place (same internal diameter as original)

These heads are worth repairing, having rebuilt 100s of these heads this is an upgrade worth doing, and a cost effective repair.

I also repair heads in my workshop, message for further details