Found this free utility to create a bit by bit copy of a flash drive
ImageUSB is a free utility which lets you write an image concurrently to multiple USB Flash Drives. Capable of creating exact bit-level copies of USB Flash Drive (UFDs), ImageUSB is an extremely effective tool for the mass duplication of UFDs. ImageUSB also supports writing of an ISO file byte by byte directly to an USB drive, useful in conversion of bootable CD/DVD iso to a bootable USB drive. ImageUSB can also be used to install OSFClone to a USB Drive for use with PassMark OSForensics™.
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