Relieve anxiety and stress, use as a sensory toy, or just pass the time having fun while pressing each officially licensed Sonic the Hedgehog Mini Bubblerz Fidget Bubble Popper Backpack Hanger. Press the Bubblerz pop bubbles down and they make a slight sound; then flip it over and start again. Collect all four Sonic the Hedgehog characters, including Sonic, Knuckles, Tails, and Amy Rose. This item comes "blind" and chosen at random.