A decorative attachment for baseball-style caps includes a plate having a planar body foldable to an arcuate configuration. The plate is detachably secured to the headband size-regulator strap of the cap via a coupling means. The decorative attachment further includes a plate cover embellished with indicia which includes a variety of visual representations such as letters, words, phrases, numbers, formula or formulae, symbols, designs, badges, colors, devices, trademarks, logos, and ornamental elements associated with a particular theme.