Features: Extremely low power consumption, each full charge can sustain 15 days reading Passive lighting and diffuse surface relax your eyes and reduce eye strain The standard interface of SD card enables you to add books unlimited Cute, light and thin Easy to take Lessen travel pressure and add more amusement Specifications: Display: 6-inch e-ink electronic paper Resolution: 800 x 600 pixels Gray scale: 8-level gray scale CPU: Samsung S3C2440 400MHz Operating system: Linux Format text: TXT, PDF and FB2 Images: JPG and BMP Extend memory: SD card 4GB (up to 8GB) Power supply: lithium-ion battery 1,000mA (compatible with Nokia BL-4C battery) Download: USB 2.0 (HS) Audio: MP3 Languages: English, Russian, simplified Chinese and more Dimension: 184 x 120.5 x 9.9mm Weight: 160g (approximately) Operating temperature: 0 to 40?C Storage temperature: -20 to 55?C