Model name PRS-650 Power source Built-in rechargeable battery: 3.7 V DC, 940 mA USB communication: Hi-Speed USB (USB 2.0 compliant) Battery life (continuous playback) Maximum Battery: Approx. 10,000 continuous page turns when reading only *1 *1 Measured using a text based content in ePub format and a fully charged battery, consecutive page-turns at approximately one second per page under the recommended operating temperature. Actual battery life may vary based on usage patterns and individual device. User available capacity Approx. 1.4 GB after initial setting Depending on size of pre-loaded excerpts, available memory capacity may vary. Operating/charging temperature 41°F to 95°F (5°C to 35°C) Dimensions (w/h/d) Approx. 118.8 × 168 × 9.6 mm (4 2/3 × 8 3/5 × 19/50 inches) Mass Approx. 215 g (7.58 oz.) Display: 152.4 mm (6") diagonal electrophoretic display 600 × 800 pixel, 0.151 × 0.153 pixel/mm 16-level gray scale Expansion slots Memory Stick PRO Duo™ slot, SD card slot