Intellivision II is a home console released by Mattel in 1983 as a cheaper model of the initial model Intellivision. When the Intellivision II launched there was no game inside the package, however this fact changed later. BurgerTime game was included in the United States sold models and Lock'N'Chase in Canada models. At the end, Brazil was the only country that Intellivision II sold outside North America.
As mentioned above, Intellivision II was cheaper to manufacture and sold than the origin model, with a more modern design and a little bit slimmed down. The controllers became also detachable and their feel became a little bit stiffer.
The only big difference of the new model was System Changer. System Changer, released in 1983 also, was actually an Atari 2600 clone that the user can connect to Intellivision II as an accessory so the user can play games of Atari 2600 with Intellivision II. This accessory gave Intellivision II the ability to make it's game library much richer.
Lastly, some of the Coleco manufactured Intellivision games did not work on the Intellivision II, so Mattel attempted to lock out third-party games. However, after this change Mattel's own Electric Company Word Fun game couldn't run on Intellivision II. Other than some other minor game and sound glitches, these were the differences between Intellivision and Intellivision II.