Honestly I take mine out. I had a few customs arrive to me with that tag that says custom falls right off.
The adhesive side should have a little silver RFID tag. Then the red plastic or black if custom . But once taken off it just looks like a black spot on the frame .
The other option would be some super glue I think
Appreciate the help! I figured super glue was the logical choice, but wanted to double check.My frames don't have any RFID tags on them, just the plastic bit. In case they pop out, dab of superglue does it.