SKU number or alias?

When I have some product with the same name but different in other ways, I have a Q, just to be sure:
what is the unique product identification?
SKU number or alias?
Is it OK to be the same (Alias = SKU). My SKU number is never the same
thanks

reg. Kai

Hi Kai,

You must use different SKU and different alias for them.

Sincerely, Giang

Hi Giang
I thought SKU was the identifier.
But I got some mix up om my page
So I have to changed, so I was hoping that I could use the SKU as alias also

Thanks
reg. Kai

OK Kai!