What is under the battery?

Hey, I was removing a battery from a Moto X 2nd gen, but unfortunately the adhesive strips broke forcing me to pry it off from the other side. But unfortunately there was a sheet still partially stuck to it, which i ripped in the process… Any ideas on what it could be as I probably need to replace it.

thanks

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Yup it was the NFC coil that I broke. Just a note for anyone else doing this repair: if the adhesive strips don’t fully come out be VERY careful prying underneath the battery… since I found out the hard way

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