Leftover part after Volume button cleaned

I changed the battery and cleaned the Volume button on my iPhone 4S, everything seemed to go alright but a part fell out while I was tilting the phone to lift out one of the phillips head screws I had removed. I went through a lot of tear down pictures and looked for other posts that might have that part left over. It is a short piece of metal braided tubing that appears to have foam in the center. About 2mm long and about the same width when flattened.

I have it next to the pentalobe dock connector screw for scale. I thought the cell signal was gone at first because the phone showed "searching..." in the bar indicator, I switched in and out of Airplane mode and it seems to be fine now.