During the lifespan of the Sega Master System, the internals of the system had been altered multiple times, as well as the external shell. The Master System was also officially bundled in certain packages - a list of these packages and model variations can be found below.
The Master System is an alteration of the Sega Mark III console, released for the American and European markets. The console uses wide rectangular 50-pin cartridges, while the Mark III uses a tall rectangular 44-pin cartridge.
Master System II
Master System III
A newer variant of the Master System II was released by Sega's Brazilian distributor Tectoy.
Master System Compact
Master System Girl
A Pink model of the Master System released by Tectoy.