I guess this has already been covered somewhere..but, what exactly do the words of the 10.3 section of the SVA Manual mean??, I presume that 'surfaces contactable by a sphere of..' does not mean that a sphere of 165 or 100mm has to fit on the mirror surface of interior or exterior mirrors - it can't otherwise interior mirrors would be huge, but just what, exactly, does it mean?

If you have 'conventional' car mirrors that are adjustable from inside the car you have a gap between the edge of the glass and the surround.

My interpretation is that the sphere mustn't be able to touch the edge of the glass. i.e. the gap mustn't be too wide. This seems to be supported by the 'reasons for failure' column.

If you have fixed glass mirrors I don't think you will fail.

It also means you can't just glue a bit of glass to a stick

Thanks for that. The wording also seems to say that non E mirrors are OK so long as long as they have 'equivalent characteristics' is this so too?