Due to the simila rity of these models this page has been combined.
The Sanyo M4430 and M4440 are near identical models of portable cassette player. The M4430 and M4440 were produced in Japan around 1975. the main differentiating factor is the color, the M4430 is seen with a white Shell, while the M4440 has a deep red shell. As far as I can tell, the M4430 was sold to US markets while the M4440 was sold internationally.