Logic board component ID

Hey All!

After getting caught in a downpour my Macbook Air suffered some water damage inside my backpack. Somehow whilst cleaning the logic board I scrubbed a chip clean off of the board and into oblivion! Since I'm in China and language barrier is a problem it would help if I could ID the component before going to a repair shop so I can tell them exactly what is missing.

The board is 820-3435-A. The part in question is in the top right circled in pink.

Thanks in advance!!