From The Manufacturer:
The Dell Axim X51 delivers performance, connectivity and a brilliant VGA display in a sleek, sophisticated design. Powered by the Intel XScale PXA270 Processor at 416 MHz, 64 MB SDRAM and 128 MB Flash ROM, the device offers excellent performance.

This handheld comes equipped with the Microsoft Windows Mobile 5.0 operating system. It includes an integrated CompactFlash card slot and Secure Digital/MMC card slots for flexible expansion.

Featuring a 3.5 mm headphone / headset jack for headsets. The integrated Bluetooth wireless technology offers flexible connectivity options!