Clear plastic yo-yo, each halved filled with Willy Wonka's candy-coated Tart N Tiny candy. You dispense the candy by using a coin to unscrew the plug in the side of either halve. No. 7154
The back of the packaging points out that "The yo-yo must be balanced for top performance. Place equal amounts of candy in each side of the yo-yo. Take candy out of the yo-yo in equal amounts."
Of interest... To see all hollow filled yo-yos in this museum, in the left panel, select Exhibits. In the right pane, in the Name/Model field, type filled, then select Browse.