Mouse. Sold bundled either stand-alone or with Cheese or Cheese 2. The following bundles were offered:
- MS-10 included Cheese on tape
- MS-10R included Cheese on cartridge
- MS-10R2 included Cheese 2 (for MSX2) on cartridge
- MS-10S did not include software (mouse only)
The actual mouse is the same in all cases, and has the marking MS-10 on the bottom.