Specifications and Features :
Introduction	Offers both thick (clamshell card) and thin (ISO) cards, both available in read-only and read/write version Operates at 125kHz (standard), with encrypted access The read-only version contains unique, tamper-proof code (64 bits), that has been factory programmed The read/write version is composed of 128 bits of EEPROM, offering different access possibilities These cards are used with matching readers, GK4001 reader for read-only cards and GK4011 reader for read/write cards The chip used in the cards require no battery for operation, receives power from its built-in coil in a magnetic field generated by a matching reader device The chip continuously transmits 64 bits of data stored in an EPROM array whenever the chip is in the field range The output data is modulated using Manchester Coding with a bit rate corresponding to 64 periods of the field frequency The chip function is obtained/transmitted by adjusting a capacitor in parallel with an external coil to generate adequate resonance
Clamshell card	Contactless card 125kHz carrier frequency Read range: 8cm to 14cm Dimensions: 86 x 54 x 1.9mm Read-only version: 64 bits Read-write version: 128-bit EEPROM array Uses matching read/write reader: GK4011
SO card	Contactless ISO-standard cards 125kHz carrier frequency Read range: 8cm to 14cm Dimensions: 86 x 54 x 0.81mm Read-only version: 64 bits Read-write version: 128-bit EEPROM array Uses with matching read-only reader: GK40

• EM9991
• BC80
• RFID Card/Tag
• EM99XX
• BC20