How to tell the difference between a Ontario Rat 1 Clone and the real deal?

[colubrid]

I see that the clones now say Rat 1 on the tang.. whereas before they said Rat 3 .

So how can one tell if they have a fake or not?

What are the tell tale signs?

Thanks!

Oh and by the way..., I did a search on the interent and can't find any info on how to tell the difference except that the clones are heavier ... But how does one know if they only have one???????