Sources tell me that this was a promotional item for Hummingbird Toys, at the time the Smother's Brothers yo-yos were a hot item. These were given as samples of their products to potential customers, and at trade shows. It shows the Smother's Brothers logo on one side, and a Hummingbird Company logo on the back. A standard Smother's Brothers yo-yo would have the Yo-Yo man logo on the reverse.