Model # NWZ-S544 | This model is also known as: NWZS544, NWZS544B, NWZS544BC, NWZS544BLK, NWZS544BLKBB, NWZS544PNK, NWZS544PNKBB, NWZS544R, NWZS544RED, NWZS544REDBB, NWZS544V, NWZS544VLT, NWZS544VLTBB, Serial Number Location: On the back of the unit. |