Speaker cable

Electrical conductors sometimes use copper for the hot leg and aluminum for the neutral and / or ground . This is true when they pull raw wire through conduit and when they put terminals on receptacles. The aluminum is cheaper, has a higher melting point, and the task is considered less critical to the purity of the voltage.  Often amps have a 4ohm tap, an 8ohm tap, and a common tap. The common tap is ground. Same idea. Not saying I agree with it, just offering this as a matter of explanation. 

I wouldn’t use it, but It’s probably copper Red and Aluminum black. It’s cheap and helps when plugging things in.  Like everyone else, I used lamp cord a hundred years ago and one side was smooth and the other had a line or lines on it. Sort of the same idea.

Chinese don't have anything OCC it's just a scam.

Better quality cable is identical wire quality,  only the connectors are red and black.  This ensures that you match the polarity of both channels. 

This gives you the best bass response. 

That's all. 

Marketing tactics meant to fool the gullible.