In the mid 2000s, Duncan sold Yo-Yo Party Packs, including the optional Add-on Kits seen in this exhibit. Like the larger party pack, this kit let you apply stickers to the yo-yo or design your own side caps.
Each add-on kit included:
• One Duncan yo-yo (ProYo model; a plastic modified shape, rim-weighted, take-apart yo-yo that featured a patented replaceable wooden axle sleeve)
• Two magic markers
• Stickers
• Four blank yo-yo sidecaps
• Two lens caps
