These white tri-fold cards feature a 2-1/4" x 3-1/4" cutout window, providing a great way to display or send Artist Trading Cards (miniature pieces of art that measure 2-1/2" x 3-1/2" and are traded and collected around the world). ATCs slide easily into the window pocket producing a clean matted effect. There are six 3-1/2" x 4-7/8" cards and six corresponding 3-5/8" x 5-1/8" envelopes per package.