A Piece Of History Novelty License Plate Hat. Show off your style with our mounted 4" x 2.2" metal patches on our 6 Panel SnapBack or Velcro Closer Hats. Choose between our different color and style caps. Our metal patches are made out of .025 grade aluminum and the designs are dye sublimated onto the metal to give a quality high gloss finish. Our metal patches are firmly attached using double cap rivets to give the patch an elegant tight fitting look!