Sony SRF-30W FM Walkman - Red and Silver
The Sony SRF-30W Walkman FM radio is commonly found in a case with a silver color (right), but it was also produced in a red case. Other than the difference in color, the radios are the same model.
As you can tell from the photo at left, the red light indicating stereo reception tends to blend in to the color of the case. You also get a good view of the single volume control on the SRF-30W, contrasted to the dual volume controls on the SRF-40W. Otherwise, both models are very similar in appearance.