That looks very close to or might be the mirror that Brett at Portland's Bike Gallery developed. While he was developing that, I was using the much smaller 3rd Eye mirrors that clamp onto the helmet visor but making a little bracket that screwed onto the visor. The much smaller mirror much closer to the eye gives almost the same field of vision and is far less clumsy to wear. Gets knocked out of kilter far less often. I had each on identical helmets and always grabbed mine.

I make my brackets by bending some 8 mil aluminum sheet to fit the visor, fiberglass both sides with light cloth and epoxy resin, then bolt onto the visor with very small screws, nuts and lockwashers. Mirror sits exactly where it should be with no fussing at all. Now, why the helmet companies and the mirror companies cannot come up with a standard so anyone could just buy such a bracket for say $5 instead of having to custom make it is completely beyond me.

Edited for some significant typos

Ben