No, they don't make an A4-sized e-reader, they just falsely claim to (as does Fujitsu with apparently the same display). Per their specs, the 13.3 inch screen is 202mm×270mm.
The e-reader itself is slightly larger than A4, at 224mm×302.6mm. Since the front case of the device is white, zooming in slightly would give a reading experience similar to holding an A4-sized piece of paper, when reading documents with white margins.