This card works the same as the normal IC cards, for 1K S50 standard. Only the Sector 0 Block Zero which is known as the Serial Number/Manufacturers Block(Chip CUID) could be programmed to any UID you want.<br> CUID card block 0 (UID's block) can be modified arbitrarily.<br> block 0 directly with normal mif read-write device modification.<br> Frequency: 13.56 MHz<br> Capacity: 1k bytes EEPROM memory<br> Rewrite Times: 100,000 times<br> Read Distance: 0 ~ 10 cm(depends on the Reader)<br> Initial Key: FFFFFFFFFFFF (12F)<br> common 13.56 mhz rfid reader writer and nfc phone can not write the particular cards!<br> Colour:random color , don't accept the specified color<br> Material:ABS<br> Package Contents:<br> 10 x CUID Tags<br> Only the above package content, other products are not included.<br> Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.