Kishu Irojōshitsu Cosmos, Thickest Grade, 50 sheets. Kishu Irojōshitsu is a long-selling colored paper that has been highly regarded for its stable quality for many years. It is popular as printing paper and OA paper because it prints well with both inkjet and toner printing. Regarding size: This is A4 standard size (210 x 297 mm), but it can be processed to sizes smaller than A4 standard upon request.