Heavy Duty Lugs - 6 Gauge Wire - 5/16" Post - 2-PackCable Gauge: 6Screw Size: 5/16"ANCOR Marine Grade lugs are manufactured from heavy duty annealed tinned copper, providing for maximum current flow100% tin plated copper resists corrosion from salt and moistureSeamless barrel design allows for maximum strength when crimpedClosed end design seals out moisture so cables stay dry and corrosion free