I am busy with my Stihl 08s chainsaw, and ordered a new clutch, when it arrived I noticed that the clutch "shoes" have a lining similar to brake shoes, while my ones are just plain solid steel, also I must point out at this point that both of these versions have a keyway securing system, however I was told by the supplier today that there is also a variant of the clutch operating on a reverse thread system, I suppose that one learns something new every day, I would welcome any comments.