When the Bee was popular, many unusual things were being tried to improve performance, and "beefcaking" was one of these. Several brands tried it, including Spintastics. To widen the yo-yo, 2 bearings were put in place instead of one, and the line between them acted as a guide to center the string. Nice concept, but it never quite worked. Remember, this was before the popularity of bearings that were shaped or konkave to center strings, and extra wide yo-yos for unresponsive play.
Only 100 of these were made, and Playmaxx never tried it again.