HLPMCW-R12-4PL, Lockbolt Break-Pins (Unified), Huck, Hucktainer Lockbolts, Style : 63253, Grade : 2, Fractional Diameter : 3/8 Inch, Body Material : Steel, Material Detail : Low Carbon Steel, Finish Detail : Zinc Electroplated, Clear Trivalent Chromate, ASTM B-633, Underhead Length to Breakpoint : 0.338 Inch (8.59mm), Drill Size : Z