All the Chip has Unique ID pre-programed,4 byte UID,And UID Can't change
Description
1. M1 Chip
2. 13.56MHZ
3. Blue color
4. ABS Material,waterproof.
5. With metal ring.
6.block 0 can't change,UID Can't change,please contact with us if you are not sure about your chip.
7.ISO14443A