I believe the image shared by @SteffanDonal is the chip inside of the Astari.
But I can pull it apart. I’ll just wait a moment for the bracelet to arrive, in order to determine which one is easiest to do so with.
Scanning the chip reveals this:
** TagInfo Scan (version 5.0.0) 03-Jun-24 15:50:52 **
Report Type: -- IC INFO ------------------------------
# IC Manufacturer:
Unknown Manufacturer
# IC Type:
Unknown IC implementing ISO/IEC 14443-4
# NFC Forum NDEF-compliant tag:
Type 4 Tag
# MIFARE applications:
No known MIFARE applications found
# Application information:
Type 4 Tag v2 application present
Proximity Payment System Environment (PPSE) present
MasterCard card
* Label: "DEBIT MASTERCARD"
* Priority: 1
Unknown application
Let me know if you want the full Taginfo report.