Are manufactured with Ancor's premium UL1426 tin copper battery cable. Flame retardant, UV inhibited, rated to 600V and 105° celsius. Lugs are tin copper to avoid corrosion and last longer. Each end has a piece of Ancor's adhesive lined 3:1 heatshrink tubing placed over the electrical connection. The heatshrink tubing seal out moisture and other corrosive elements found in the maine environment.