Detailed Description  Digital E-Book Reader E501-D  E501-D Installed with the latest E_Ink technology, eBOOK is the lightest and thinnest electronic reader in the world right now. The reading effect its present completely equate to traditional ones. Good manufacturing state-of-art, streamlined key design and simple operation method all make it enjoy a wide popularity. The standard interface of SD card enables you to add books unlimitedly. Paper like, high contrast Light weight Low power consumption SD card slot expandable up to 4 GB MP3 Support: TXT PDF BMP JPG Less power consumption. Ultra-long reading time. No power requirement after display. A full energy charge is sustainable for reading of thousands pages. Cute, light and thin, easy to take. Lessen travel pressure and add more amusement. Support MP3 files and add more pleasure while reading. Dimensions  188mm(L)×118mm(W)×8mm(H) Weight  176g ( Include battery) Display e-ink 6 Inches 800×600 pixel 4-level gray scale Input  Key CPU Samsung S3C2440 OS Linux 2.6.18 Storage  SD/MMC card( expandable up to 1GB) Power Supply  Li-ion 3.7V,800mAh Operation Condition  0-40 Storage Condition  -20-55  Other  MP3 Built-in