CB Radio QSL cards from Place Stamp Here: The Pie Shops collection.
These QSL cards were used by CB radio amateurs to confirm their two-way radio contacts with each other. When a CBer made radio contact with someone they sent a personal card (usually postcard-sized) with their handle, call letters and location as a souvenir of their interaction. These are generally from the 1960s to the early 1980s. Any questions? Ask away or e-mail me at firstname.lastname@example.org