The Sony WM-FX 31 is a portable cassette player, also known as a Walkman, manufactured by Sony. It was released in the late 1990s and is part of the WM-FX series. The player features a built-in FM/AM radio tuner, cassette playback and recording capabilities, and an LCD display. It runs on two AA batteries and has a headphone jack for audio output. The WM-FX 31 was a popular choice for portable music listening during its time.
