According to Dean's Cards website, Pre-War cards that were inserted into dairy products are known as "F-Cards." This category of cards is considered a miscellaneous classification and were often found in milk, eggs, and ice cream, as well as in other products such as beer, cereal, flour, peanut butter, and soda.
One release found in this group is the 1928 Sweetman, which is the set this custom Brett Lawrie is modeled after. The Sweetman's contained 60 cards in the set, each measuring 1 3/8" x 2 1/2"; and although it has a name and address on the back, the product they were advertising is unknown. Had I been thinking, I would have done better to model the back after one of the many ice cream companies whose cards were nearly identical to the Sweetman. There's a mention of their ice cream products on the backs of their cards.
Since the popular Cow ice cream company is based out of Canada, I choose a Blue Jay for the subject matter. Why Lawrie? Well, for one he is a Canadian who is an up and coming superstar. Besides, I think the man might have more tattoos than Cow ice cream has flavors (32+).