This is a label for a Retrode SMS plugin with the Game Gear cartridge port installed.
Wanting to combine the styles of the SMS and the Game Gear, I went with the late SMS/early Brazilian Game Gear small checkerboard styles, with white and gray colours.
Lettering uses Gelosia, a Georgia font drop-in. The label was created using Inkscape.
The Game Gear "Master System" style image comes from this Sega-16 article.