deskthority

How did you know that this is TK-80? Is there any way that we could see (and preserve) or reference that fact? (Since we have no other model information and Tokai are no longer around to ask.)
I have a few MM9-3 with the diamond TKC logo from old Seimitsu arcade buttons. That and the rivets ...

This is the primary switch type used in Japanese arcade buttons. Sanwa uses snap-together clones of this switch with linear feel, while Seimitsu uses the original riveted tactile TKC MM9.
https://www.akishop.jp/button-parts/149-sw-68.html##
https://www.arcadeworlduk.com/products/seimitsu-mm9-4 ...