Marine-grade wiring provides peace-of-mind when you're far from shore.Sophisticated marine electronics and instruments only operate at peak potential when supplied with power at the right voltage, which necessitates high-quality wirelike Ancor's Primary Wire. Ordinary automotive-type wire can suffer a loss of conductivity after a few months in the marine environment. Corrosion takes place, and corrodes the copper conductor, when the wires jacket and insulation are compromised by water intrusion.Marine-grade wire from Ancor is rated for oily and wet environments because its jacket is impervious to those conditions. Each strand has a tin coating for extra corrosion resistance (note the silver” look whenyou strip it).Vibration is always present on a boat, and will quickly fatigue and crack coarsely stranded wire. Ancor wire is Type 3 stranded, meaning that it has 5-10 times more copper strands than Type 2 wire, making it moreflexible and fatigue resistant. It is constructed with premium vinyl insulation that is rated at 600 volts, 221F (105C) dry and 167F (75C) wet. It is also Marine UL-listed, and meets the highest ABYC standards forAC and DC use. Finally, it is based on AWG (American Wire Gauge) wire sizes, which are 6-12% larger than SAE gauge wire. So you get more current-carrying ability than from similar SAE wire.Ancor Primary Wire Bulk Spools Chart