The Commodore SX-64 was a variant of the Commodore 64 released in 1984.
The Commodore SX-64 was intended to be a more portable alternative to the Breadbin Commodore 64. It did not see much success however, due to many reasons. It was extremely expensive, and it was actually rather heavy, which meant that it was only actually mobile to an extent.
Tech problems\design errors
The only SX machine to go on sale; first revealed at CES of 1984
Never made it to release, only seen at CES of 1983.