The CardBook® cardholder is a patented booklet constructed in a manner similar to a passbook or passport, but in a wallet size format with a pocket inside either the front or back cover to hold a card and protect any encoding on a magnetic stripe or microchip. The CardBook® cardholder measures 2 1/2" x 3 1/2" and is constructed with a minimum of 2 pages to a maximum of 58 pages to provide your cardholders with instructions, reference and record-keeping.