Busbar rating of MB816B150STD

I have a quick question. On this Cuttler Hammer panel, the MB816B150STD shares the same exact panel as it's 200A counterpart. The MB816B200STD.

What my question is, is if the two panels share the same exact bus bar? Meaning, though the 150A panel has a manufacture-installed 150A main breaker, does the 150A panel still have a busbar rating of 200A? I've looked all over the panel sticker and it does not provide a busbar rating.