Are you a Flintsones fan? Not you? Bet you know someone who is. And we can almost bet that they don't have one of these.
This yoyo (sic) was made by the Union Wadding Company in 1978 for Hanna-Barbera Productions. Most likely it was made to follow up on the success of the Pebbles and Bamm-Bamm cartoon show which ran in the early 1970s.
The yo-yo is mint, and the card has some raised areas and yellowing from age. There is what appears to be a puncture near the first "Y", perhaps from hanging on a peg. There is also a ding on the blister pack which can be seen in the photos.
There aren't too many of these around in this fine condition.