Sleeves are made of Copper or Brass and are available Nickel plated and Black oxidized. Sleeves can be fitted to wire, monofilament, and other various lines. When matching sleeves to wire, use single-barrel sleeves with an inside diameter of more than twice the wire diameter you are crimping. Burr-free nonabrasive finish combined with high strength and corrosion resistance makes AFW?s sleeves the preferred choice of professional leader, lure, and tackle manufacturers.