ERGO STEEL 2 STAINLESS-STEEL Knife Edge Maintenance Sharpening Tool Straightens and prolongs the edge life of knives. Ideal for knives of any length. All Stainless steel design for improved hygiene and durability. Wide knife entrance easily guides the blade to the 4 alignment rods for a perfect edge in seconds. Specially developed flexible stainless steel alignment rods provide superior durability for straightening knife edges.