FCC ID Search

To find out details about devices you plan to buy,
see the electronics inside, see RF test results, etc.

https://youtu.be/iFQy19CPNmM
https://youtu.be/nHzSJKqtTa8

https://www.fcc.gov/oet/ea/fccid

i didn't try/need it myself,
but it may be useful somehow.