This vintage ad is an early example of cobranding, Rice Krinkles had a series of Mustangs inside their cereal box, little toy cars that came in Arcadian Blue, Signal-Flare Red and Springtime Yellow just like the real ones!
Post's Rice Krinkles mascot So-Hi (named so because he was "so high" as in a short little fella), shows us this by allowing us to see a young boy and his mom driving home from the grocery store. You won't see So-Hi anywhere on the grocery shelves today as the mascot is now deemed offensive to both asians and little people (though, I always though So-Hi was a child). Post's Rice Krinkles cereal had an unfortunate lineup of mascots, with the more popular So-Hi taking over after a demonic clown.
Client: Mustang & Post
VO: Bob McFadden