Smog tube plating/finish ??
 

What plating/finish is used on 1969 smog tubes? Thank you,

I think originals were Black zinc, or Black Phosphate is probably acceptable too. My originals almost look grey but are probably faded, kinda like my hair. LOL.

I have 3 survivor type low mile systems. All 3 almost appear like a root beer brown anodized color for lack of a better description.

Almost look like oil rubbed bronze. I don't know anybody who can duplicate it...Joe

I showed a old brown/ bronze smog tube to our plater, he had now idea on what it was. He could do olive.
Most likely they are bright plated then dyed. So looks like black zinc my be the only way today ?
Mike