EWCS 4 Gauge Premium Extra Flexible Welding Cable 600 Volt Combo Pack - Black+Red - 15 Feet of Each Color - Made in The USA

Used for marine wiring for 2nd battery.

Good quality. Easy to work with.

Like others already mentioned, this wire feels heavy, which immediately reassured me that its not copper-plated aluminum even before I opened the package and had a chance to inspect the strands. For reference, aluminum density is 2.7 g/cm3, while copper is 8.96 g/cm3. So if youre looking for a real copper wire, this is the one. Buy with confidence and you will be amazed with the quality.

Great