How can you tell the difference between an authentic CHI flat iron vs. the knockoff?

I'm considering ordering one from eBay, but I have no idea how to tell if I'm getting the real deal.How can you tell the difference between an authentic CHI flat iron vs. the knockoff?
You're best off just getting one from the local beauty supply store, those are always authentic.How can you tell the difference between an authentic CHI flat iron vs. the knockoff?
Well CHI Stands for Ceramic Hairstyling Iron, so first make sure it's ceramic. Second.. E-bay has cut down ALLOT on knock-off merchandise so if it says CHI or has a picture of a box that says CHI you are probably safe .