Second row seat head rests?..

[PARAGON]

I shouldn't have said base, sorry about that. If you look at the headrest where the posts go into it, you'll see a detent on one side or the other. The posts remain with the seat and only the headrest sans the posts come out. So, no, it's really not like the front.

[PARAGON]

Without looking, I think the little detent things are on the rear of the headrest, one for each post.