What does 'cone facing down' mean on a rubber gasket?

[BustedFlush]

Does this mean the thinnest end facing down, or the thickest?

I know this might be really obvious to most people, but I'm working with a rubber gasket on a fluidmaster button flush. It doesn't really resemble a cone at all.

Is cone a common term?

 

[Charnwood]

Do you mean the black washer that reduces a 2" cistern outlet hole to accept the 11/2" valve outlet or the replacement white washer that goes into the valve?
If it's the black one, and you are fitting the valve into a cistern designed for a 2" outlet valve, the bit sticking out of the centre of the washer (the cone) needs to go into the cistern outlet hole.
This picture shows it laying upside down:

 

[BustedFlush]

Hi mate, thanks for getting back to me but I got it sorted. It was a black rubber gasket for 2.5 inch (ish) outlet.

Cheers for the help anyway.