Released in March 1996 in Japan and later in other territories, the HST-3220 model SEGA Saturn is a minor hardware revision of the SEGA Saturn that changes the shape of the power and reset buttons to be circular and the open button to be more rectangular. The glossy plastic fascia where the power and access LEDs on the HST-3200 and HST-3210 models has been removed alongside the access LED altogether. Outside of these cosmetic changes, the hardware is identical in functionality to the HST-3200 and HST-3210 models.

This cosmetic change was initially done in Japan to make the console appeal to a wider demographic with a brighter, friendlier colour scheme aimed at a younger audience. This did not carry over to Western markets where both console revisions are moulded in black plastic.

The HST-3220 model SEGA Saturn is also the first Saturn to ship with the redesigned MK-80313 control pad which featured a slimmer form factor when compared to the original MK-80100 controller.

From: https://www.segadriven.com/sega-saturn-model-mk-80200a-50/