1X30 Ultra fine sanding belts have a cushioned "scrim" back and are constructed on an ultra flexible mylar backing allowing the belt to conform to contours and evenly polish your blade or handle. Micron and Grit Scale rated to apply accurate finishes. Aluminum Oxide Grit material offers a consistent cut resulting in fine finishes. Ideal for many ferrous and non ferrous materials commonly found in Knife making like brass and copper.