Identify Plastic Part?

Does anybody know what the un-labled large cut out in the centre of the unit that has some black plastic in it actually IS?

Question moved from an unrelated thread. Can you be more specific about what piece you’re referring to? Do you mean the cutout in the midplate under the keyboard visible in this picture?

If so, that is the interposer, which connects the expansion bay to the mainboard. It’s shown in step 7 here: Install Graphics Module - Framework Guides

That IS the part, that is numbered one (from memory), but is NOT mentioned in the instructions.

Again step 7 - the mid plate cable?

The mid plate cable is at the bottom right, with the orange tab.

The piece in the middle is the interposer, which is mentioned in at least 4 steps in the guide I linked above.

It IS the “Interposer” that I was referring to Christian which is NOT identified (but numbered 01) and I was just asking about it because it is NOT mentioned in the video that I used to assemble my kit of parts.
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