Pocketbook PRO 902. Diagonal: 246.4 mm (9.7 "), Technology: E Ink, Gray scale levels: 16 levels of grey. Document formats supported: CHM, DjVu, DOC, ePub, FB2, FB2.ZIP, HTML, PDF, PRC, RTF, TCR, TXT, Audio formats supported: MP3, Image formats supported: BMP, GIF, JPG, PNG. Maximum memory card size: 32 GB, Internal RAM: 256 MB. Interface type: USB 2.0, USB connector type: micro USB A, Headphone connectivity: 3.5 mm. Operating system installed: Linux