

The later Master System II redesign removed the card slot, turning it into a strictly cartridge-only system and is incompatible with the 3D glasses.

Accessories for the consoles include a light gun and 3D glasses that work with a range of specially designed games. The original Master System models use both cartridges and a credit card-sized format known as Sega Cards. A cost-reduced model known as the Master System II was released in 1990 in North America and Europe.

A Japanese version of the Master System was also launched in 1987, which features a few enhancements over the export models (and by proxy the original Mark III): a built-in FM audio chip, a rapid-fire switch, and a dedicated port for the 3D glasses. The Master System launched in North America in 1986, followed by Europe in 1987, and Brazil in 1989. It was originally a remodeled export version of the Sega Mark III, the third iteration of the SG-1000 series of consoles, which was released in Japan in 1985 and featured enhanced graphical capabilities over its predecessors.
