Geberit toilet flush

Hello...i have bought some bathroom furniture which uses a "Geberit" slimline WC flush tank.
On the flap of the tank is a printed diagram which shows what appears to be a needle valve being removed from one of the components and then washed under a tap.
Can anyone tell me what this signifies?
Also...there are another 2 sections shown with parts being removed and washed....what's going on?

Thanks for help.....Mike

could be .......the old man from Cosham who took out his ****** to wash `em ........his wife said, Jack, if you don`t put `em back ....I`ll tread on the buggers s and squash `em or it might refer to the "quiet ballvalve" Torbeck type

Hi...I was hopeing for something a little more positive than your personal habits...perhaps someone else would be more informative.

many thanks....Mike