The Minnie Mouse MagicBand came out December 14th, 2014. Disney’s merchandise SKU barcode for this MagicBand is 400009290431.
This band actually had two designs. Below, the original older design is on the left side, and the updated design is on the right. Notice how the polka dots fill the entire band near the Mickey head on the updated design:
On March 30th, 2017 the MagicBand 2 version of the band came out. The barcode SKU for it is 400020130037. There is a slight design change with this band in that the little mouse head at the end of the band strap isn’t white on MagicBand 2 like it was in the original graphic as seen above.