The X-ACTO Designer Series #1 Craft Knife offers superior precision cutting and ergonomic control. Our #1 craft knife is perfect for cutting lightweight materials, such as paper, plastic, balsa, thin metal, cloth, film and acetate. Made with a rear blade release and safety cap, this crafting knife was designed with safety in mind. The #1 Craft Knife also includes a #11 blade, and can be fitted with No. 10, 12, 13, 16, and 17 X-ACTO blades.