Primato lockring

Has it got a different thread to the system x/formula etc type hubs?
Went to switch the cog from my system x to the primato hubbed wheel i bought from ebay and have been using with a freewheel, anyway the primato wheel didn't come with a lockring but i thought id be able to use the system x one but it won't fit.
Punctuation/sentance structure fail. Sorry.

Miche lockring thread is Italian like Campy and Phil ; others Shimano/Formula Asian manufactured are all ISO standard.

ah right cool. Thanks.

Had the same issue. This thread has saved me from some agonising over said miche thread, thanks....need a new lockring then.

Also had the same issue. What amazed me was that my wheel builder didn't know either that lockrings came in different sizes. Until I showed him Sheldon he insisted that the lockring he gave me was correct and it was user error.

Hubjub has this:

"Bringing up the rear of our quintet are these Miche lockrings. They use the (now rather obscure) French threading, meaning compatibility with Miche and Mavic hubs plus some other vintage offerings."

I was thinking of buying EAI's lockring for Miche hubs, but reading that made me worry.

Anyone?

Does the EAI ring work?