Buy Secrid Twinwallet (Original) Boarding Gate Buy Secrid Twinwallet Nile Black Online William Penn Secrid Twinwallets Double Capacity Slim Design Travel Universe Buy Secrid Twinwallet (Metallic) Boarding Gate. With two Cardprotectors to hold double the content, the Twinwallet carries up to 16 cards, banknotes and receipts, but remains compact in size. Together with its sturdy closure and exterior, to hold extra cards, banknotes and receipts, the Twinwallet holds much but remains compact in size. Holds A maximum of 8 embossed or 12 flat plastic cards Up to 4 extra cards in the exterior wrap Banknotes Business cards Receipts