A card assembly includes two spaced-apart circuit boards defining an interior region between the cards. Connectors may be mounted on the circuit boards and be located within the interior region. That is, respective interior sides of the circuit boards may face each other and the interior region. A connector may be mounted on each interior side. Mounting the connectors in the interior region provides an assembly that defines a mating footprint that is independent of the respective thicknesses, and variations in the thicknesses, of the spaced-apart printed circuit boards.