4-inch Fisher-Price Adventure People line). In any event, while Star Wars will forever be inextricably linked to the small figures, Kenner also produced what it called "Large Size Action Figures" or as most would call them, "DOLLS".
Boba came in Star Wars or ESB branded packaging. The loose example shown here took me some time and expense to assemble, as it originally came with many (easily lost) accessories.
This picture also clearly shows the small opening in the back of his helmet that contains a tiny lens. You can look through this lens and see a "Boba's eye view" of the bounty hunter's target. Pretty cool!
You can clearly also see the arrangement with the string and how it loops around the backpack hooks.
Although more 12" figure prototypes were designed by Kenner, the relative unpopularity of the large figures doomed the range, as it made much more sense for the manufacturer to concentrate on the smaller line and its profitable ships and playsets. The large figures were obviously too big to justify making ships etc. to scale, so the range was limited at the end to Luke, Leia, Han, Chewbacca, Threepio, Artoo, Ben, Jawa, Darth Vader, Stormtrooper, Boba Fett and IG-88.