These OEM foam gaskets are for the metal covers that provide access to the top of the fuel tank and the fuel pump. Over time the foam gaskets break down and crumble to dust; replace it to keep the cover from rattling and coming loose.

The oval gasket is over the actual fuel pump. The round one is over some other stuff.

Fits all 2002-2007 WRX and STI, plus 2003-2008 Forester XT.