Seimitsu Button Types

I’m looking to swap out the buttons on my HRAP 4 Kai for Seimitsu ones, but I’m confused as to the types available. I’m looking on focus attack, and don’t fully grasp what the differences are between the PS14-G, PS14-K, and PS15. Can anyone help me out with that? And I assume I’d need one of these as opposed to the screwbuttons.

Ask in this thread for this kind of question:

Mmm, will do. Thanks.

Someone on the other thread actually linked me to that exact same article. It’s highly useful. Thanks!