11-1/2 Inch Long Triangular Shaped Steel Mandrel: TJ-45477 This Mandrel Is 11-1/2 Inches Long, And Weighs 1 Pound, 0.5 Ounces The mandrel is tapered from 5/8 inch at the top to 3/4 inch on all 3 sides at the bottom The triangular design makes it easier to bend the metal into the desired shape The bottom 3 inches are rounded to make it easier to hold the mandrel in a vise Smooth sides will assure you get great results when shaping wire or precious sheet metal