A fixed-axle, one-piece aluminum yo-yo. Aluminum is brushed (or unfinished). To my knowledge, this yo-yo was only available from Y4L.com (now yoyoplay.com; checked July 21, 2015).
Hard to find.
To see all mini yo-yos in this museum, in the left panel, click Exhibits.
In the right pane, in the Name/Model field, type mini, then click Browse.
