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Can anyone tell me what these are for? (circled) This is my exact engine and application - 128M02-0423-F1 I bought a NOS Briggs and Stratton short block engine that included a gasket set.

PS
Since originally posting this I was able to figure out some of it. One is the intake manifold to carb gasket. One is the cab bowl gasket. The smallest black rubber o ring I haven't figured out yet.
I know the other two gaskets are for the valve cover/breather assembly and intake manifold.

As a side issue/question- Why is there a duplicate valve cover gasket when one is already installed on the engine from the factory? I have the same question for the intake manifold gasket. It seems like there are two variants on the "same" gasket and it's up to you to pick the correct one.

Thanks for any insight you can provide!

engine parts list above.
engine gasket set above.