Sony PRS 650R. Diagonal: 152.4 mm (6 "), Technology: E Ink Pearl, Gray scale levels: 16 levels of grey. Document formats supported: bbeb, pdf, rtf, epub, Audio formats supported: MP3, AAC, Image formats supported: JPG, PNG, GIF, BMP. Internal storage capacity: 2 GB, Compatible memory cards: MS Duo, SD. Interface type: USB 2.0. Battery life (max): 336 h