Interesting question. My 1976 Cosworth Vega has dual "sport mirrors" (painted body color, black) but the OE RH lens was flat. It was basically useless with such a narrow field of view.

Of course, Vega production ceased after 1977, but at some point I learned that Monzas and their other division clones with sport mirrors had convex lens, so circa early to mid-eighties on a trip to a Pick-a-Part I found a Monza and removed the right side convex mirror and installed it in my RH CV sport mirror housing. Wow, what a difference!

My '72 Vega GT did not have a RH mirror, and I don't recall it was an option.

At some point dual outside mirrors with a "wide angle" RH lens probably became a NHTSA standard, but I'm not sure of the exact date... probably late seventies to early eighties.

Wasn't it in the last year of two that rear view cameras are required in all new cars?

Speaking of mirrors, I think "folding mirrors" first became a European standard to protect pedistrians and was eventually picked up in the USA and probably became a NHTSA standard. Of course, nowadays most are powered to fold/unfold at the tap of a swtich, but they still fold back if they hit something.

What about those Japanese cars with the dual mirrors out at near the front of the fenders. Is that still a requirement in Japan? I can't imagine they're worth a damn!

Duke