This highly versatile Diamond Knife Sharpener comes with a triple diamond plated design. This sharpener has thousands of high quality industrial grade diamond particles permanently bonded to a steel alloy. Diamond is widely regarded in the industry as the top sharpening material. It is very long lasting, retains its flatness and sharpens both serrated and fine edge blades. Technical specification: Overall length: 7.4in Closed length: 5.35in Weight: 28g