Best explanation that I have heard on these gauges.

That was very educational, thank you.

thanks for the video

No actual showing on the saw?

Dear Sir: Other than the gauges on the extreme ends, I could not understand what you were explaining about the other cut-out's in the Stihl chain gauge as to how they relate to the saw chain. I own five Stihl saws, all used with good results, but the internal cut-out's of the gauge is beyond me? The Stihl owners manuals for each of my five saws has a picture of this gauge but the description in each of how to use it is identical and non-existant. Also, in each owners manual it states that this gauge can be used to determine if the cutters are worn out, i.e. filed too short. Again, this is not explained and is not understood.