The middle one is about the same size as a quarter.
And it's pretty hard to understand what the part numbers are for the gaskets. It came with one piece of paper and i don't really understand what it means. The gasket kit part number is 16010-HB5-305 and the gaskets i'm concerned about one has a B on it the other a C and the flat gasket was just hanging out in the main bag.
The explanation is in the paper. Many o.rings and washers are interchangeable between different carbs, so what Honda did was to simply create a single reference for similar carbs, that contains all the common o-rings plus all the individual o-rings per each carb, so you just have to discard the ones that are not used in your carb. This helps to keep the number of references down at the expense of some discarded o-rings.
Don't remember exactly how the paper was, but it was like a table with the bike model in the columns, and it would tell you which o-rings applied -A, B, C etc-
I hope I have made myself clear.