Translation: a stack of trays on one side of the xray machine, that get passed through the xray machine to the other side, where they are put in a second stack.

Translation: a stack of trays on one side of the xray machine, that get passed through the xray machine to the other side, where they are put in a second stack. The second stack can be moved as a stack (presumably on wheels or something) back to the near side of the xray.