From Craig at Zing discs:
The Cozmo took Zing into the next phase of Mini Disc development. Made one of the first 3D printed molds and shot plastic into it. Who-la! The Cozmo was made and I quickly made a permanent mold from steel in two weeks. This unique disc has a “born-on” date on each disc inscribed inside. This is a game-changer for the disc industry. This disc also mates with the Microfoil for a container set.
Specifics: Disc Weight: 38 grams: 4.3″ diameter(mates with Microfoil)
Minis are sold in random Colors / Foils.