It says nickel, but it's nickel-plated steel. I scratched one up with sandpaper and the next day I saw what I thought was rust so I sanded the end down and dunked it in a jar of salt water. The next day I sanded it, rust appeared on the surface of the lug. This doesn't happen with my other cables, they are pure nickel, not nickel plated. Another problem with nickel-plated steel is that the steel conducts half the current of pure nickel wire. Half. So I'm saying if you need power, don't useβ¦