USB card readers can be used as the connection between flash devices and the duplicator. However, only a "Single device card reader" (as photo 1) can be used. If you use "Multiple devices card reader "(as photo 2), the duplicator will not correctly identify where the data is coming from. Because of this, the duplication may fail.
Note: When you use "Multiple devices card reader" on PC, there will be more than one partition showed on the screen. For example, if you insert a 4 in 1 multiple card reader onto a PC, there will be 4 partitions showed on the screen.