- 6 Sheets Print your photographs, invites, or artwork using this ProMAGŪ printable magnet postcard. Perfect way to spread your message and ideas, this magnet postcard has a matte white paper on its one side and a glossy white paper on its other side. Use this inkjet printable postcard to put out your party announcements, save the dates, templates and photographs. 6 sheets. 4 inches x 6 inches. Magnetic matte white paper side