RFID Proximity Card 125KHz
GTscan

A proximity card is a "contactless" smart card which can be read without inserting it into a reader device, as required by earlier magnetic stripe cards such as credit cards and "contact" type smart cards. The proximity cards are part of the contactless card technologies. Held near an electronic reader for a moment they enable the identification of an encoded number. The reader usually produces a beep or other sound to indicate the card has been read. The term "proximity card" refers to the older 125 kHz devices

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