Excel 16008 - K8 Flat Yellow Adjustable Knife - Adjustable, you can adjust the length of the blade by releasing the nut. Make sure it is tight before cutting. You can use both ends of the blade. Used for cutting boxes, wood, leather, and foam. Uses Excel 20080 and 22680 No 8R Utility Knife Blades. Made in USA. Note: X-ACTO 8R blades have a larger hole than the Excel 8R Blades.