Though rarely available in the domestic market, export models featured an internal 3.5" drive, like the contemporary Atari ST or Amiga computers. Such models had both EGA and composite TV output connectors operational, as well as an AY8910 sound chip. Domestic models often did not include the TV output, the internal speaker or both. The AY8910 chip for the domestic models was sold separately as an external extension module, hanging off the same extension bus as the optional external disk drive.[8]