Different size strands in cable.

[hillbilly1]

Did they just start doing this? Or is it just certain cable sizes? Never noticed this before. 4/0 thhn.

 

[ppsh]

It's unilay stranding. Southwire uses it up to 4/0 copper, then goes to compressed stranding.

 

[hillbilly1]

I’m usually pulling much larger wire this way, never noticed it before. Two strands opposite of each other.

 

[Birken Vogt]

I have noticed many cables with different size strands, but never cared enough to look for a pattern. I think it is copper, usually.