Ancor Marine Grade Primary Wire is manufactured from tinned copper stranding for maximum protection against corrosion and electrolysis. Ultra-flexible (Type 3) stranding helps prevent fatigue due to vibration and flexing. Ancor's proprietary premium vinyl insulation stays flexible even in extreme cold (-40° F/ -40° C) and resists salt water, battery acid, oil, gasoline, and ultraviolet radiation. The wire's exclusive insulation is rated at 600 volts, 221° F / 105° C dry and 167° F / 75° C wet, and is engineered to withstand heat and abrasions. Exceeds all UL 1426, US Coast Guard Charter boat (CFR Title 46), and ABYC standards.