Doubleheader Calligraphy Marker, 6 Piece Set Let the creativity begin! Itoya's Doubleheader® Calligraphy Marker will add that special touch to all of your lettering projects. The Doubleheader Calligraphy Marker provides performance and vibrant color. Two chisel points give the option of thick or thin lines: a wide point for bold, distinctive lines and a narrow point for smaller, intricate designs.