Marantz's PM 1 1S 1, PM1S2, PM 1 1S3 have obvious differences in appearance. PM 1 1S 1 adopts aluminum alloy front panel, while PM 1 1S2 and PM1/S3 adopt glass front panel.
I hope the above information is helpful to you. If more detailed information is needed, it is recommended to contact the Malanz authorities directly.