100pcs/Lot 13.56MHz Rewrite 0 Block UID RFID Tags Writable Keyfobs ISO14443A Key Fob Used to Copy Mif Card

 13.56MHz Writable 0 Block HF ISO14443A Used to Copy Cards

This key works the same as the normal IC cards, for Mif 1K S50 standard. Only the Sector 0 Block Zero which is known as the Serial Number/Manufacturers Block(Chip UID) could be programmed to any UID you want.  

Blue, red, yellow, gray, black

If you choose Mixed color, you will get: 20 blue, 20 gray, 20 black, 20 red, and 20 yellow.