In the first place, you could see the brand print on one frame side. If it is the real one, the print should be smooth which has no flaw. You can use the fingers to feel the surface of lines. Then you should observe the balancing character of the sunglasses. If it is real, it should be symmetric in design. You can put it on the table to observe.
Hmmm, as far as I know, Armani sunglasses are one of the best in the world. And if you plan to buy a pair of them, you should prepare yourself a big budget you know? And basically there are some ways to identify h authenticity of those sunglasses . First, you should carefully examine the surface of the sunglasses, any bad spots can be a sign of fake. Also, you can call their service hotline to check it out. That would be the most useful way, since they know how to identify.