Found on the back cover.
Illustrated in red, black and white.
Ad for fictional Bubble-Nut Sparemint Gum, which costs only 5 green stamps, which is also good for blow out patches and bicycle tires, and comes in assorted flavors: charcoal grey, plaid green, people purple and sickly blue.
This sequence may out of its proper order.
Two-page humorous aboard ship shennanigans.