Yakima hasn't made Mightymounts for OEM bars in 15+ years. The only MM currently produced are to fit their new bar shapes.
Universal MM will fit to convert old Yak accessories to the OEM bars but they are a pain in the ass. Everything they make is compatible out of the box w factory bar shapes. Note that just because a mount fits the bars it doesn't mean the bars can handle the load, Rooftop tents for example.
-Yakima sales rep for 15 years.