Grey Literature has become a corner stone of the supply of scientific and academic literature. TIB is the German National Library of Science and Technology with a strong focus on Grey Literature. The acquisition of this kind of literature is not a simple process due to the unconventional distribution channels and the cost. For this purpose TIB has its own grey literature acquisition team. In order to keep the data readable and accessible in the long term TIB hosts, administrates and runs a digital preservation system which manages different kind of objects and file formats. Each group of objects needs its own workflow and ingest preparation (pre-ingest). This also applies to grey literature. Some of the grey literature publications are delivered on USB-flash-drives. In order to catalog them the USB-flash-drive will be accessed by librarians several times. As USB-flash-drives are “write-many” storage devices, accidental write or erase processes could already take place during the access by initially connecting with a PC. This fact leads to the risk of loss or overwriting of rare and expensive data. Furthermore the lifespan of this data storage and the interface dependency are two remaining basic concerns of their long term accessibility in libraries. The minimization of risks of accidental manipulation by direct access to the USBflash- drives can be achieved through the use of a USB write blocker. This device prevents all write instructions and ensures the safe forensic data transfer. The secure storage of the data from the USB-flash-drive can be done through the separation of data from the storage device. For this purpose TIB has developed a reusable, semi-automated workflow with a strong focus on usability for librarians. Using a script and the write blocker, that prevents the accidental write accesses, the workflow saves the data from USB flash devices via imaging or copying. This project consists of a market survey (4 person-days), implementation (28 person-days), tests (4 person-days) and launch in team (1 person-days). The price of the write blocker is 500$. The main focus of the paper is the detailed description of the project including its technical implementation, discussion of the results and further improvements.