Epson product code B12B819661 refers to the Passport Carrier Sheet accessory for specific high-speed document scanners.This is a specialized, rigid, protective sleeve designed to enable the scanning of passports and other thick or bound documents that cannot be fed directly through a standard Automatic Document Feeder (ADF).
 
Allows for the scanning of open passports (and similar booklets) up to approximately 2 mm to 5 mm thick, which is far beyond the normal paper weight limits of the ADF.