I understand that boards of this vintage often just have foam-and-foil switches. But you never know, it could gave something exotic like Hall Effect or Magnetic Valve switches—or even the ultra-rare Cherry MX Periwinkle!
Amazing, isn't it, how so many people who sell keyboards are clueless about what's important to know about them? How many auction listings have you seen with three photos of the cable, for example, but not one of the back label with all the ID info? And God forbid they should take the initiative to remove one of the caps. :?D