The Commodore SX-64 was to be the world’s first colour portable computer and shows once again the marketing genius that Jack Tramiel was. it was basically the C64, surrounded by a strong metal casing with its power supply located on the bottom (or back) of the unit.
The case also has a large handle for carrying it around, or for setting up the unit for use .
The keyboard also servers as the protective front-panel of the computer and has the Commodore logo in full colour on the front panel’s stripe, giving it a bit of sport’s look.
Although it has a fully compatible Commodore 64 computer inside, it was not compatible with all programs or games. Specifically, if the applications used the tape-buffer, you’d be in trouble as this was missing in the SX-64. To compensate, it had a built in compatible 1541 disk drive configured as drive 8.
There exist versions of the SX-64 with two disk drives, named the DX-64, but power constraints basically prevented them from functioning properly. To my knowledge, the DX-64 was only used by Commodore employees and I haven’t seen any on the collector’s market.