Apple Now Selling Parts for Seven New Devices Unveiled Last Month

[addamas]

I hope one day they will officially sell as independent part the “screen mounting edge seal stickers” (there might be better name for that) - the part which is cheap but not always good quality and naturally degrades over time.

So in short this seal which makes sure phone is waterproof all around between metal chassis and screen as each time you replace battery you need to add it again.