I´m planning on upgrading my P1P to P1S.
Printed the Chamber Fan Housing Yesterday and want to install it to my P1P, the Fan from the Bambustore lacks the Sponge an Screws.
So what Screws should i use now? I can´t find any recommendations on the Wiki etc.
And where can i get the Sponge? 
Maybe its relevant for the future, if more People want to upgrade to the P1S.
Is this what you mean?
Ah thats the Filter, it´s about the Housing on the back of the Printer.
The Chamber Fan is attached to the Housing and the Housing is attached to the Printer.
You can put the Air Filter in this Housing from this little Flap in the Chamber.
I really don´t have a clue whitch Screws i should use to attach the Fan to the Housing and the Housing to the Printer. That´s what i´m up to.
On the P1S and X1C there is this Housing allready attached and the Fan got some sort of Sponge/Foam on the backside to the rear Cover (i think to prevent from vibrating the Metal Back Cover).
Apparently the fan just rest on the 4 nubs of the housing and presses against the back metal. No screws are indicated.