How much does an iPhone 5S weigh in the box?

I'm trying to work out how to tell if a box contains a genuine iPhone or a fake by the weight. Thanks for your help! Needs to be an iPhone 5S box with accessories.

Added (1). Should be between 350-450g - don't bother giving me the shipping weight, I need the exact weight.

About 7.4 Pounds

It's an interesting question. Has some weighed a iPhone with the box. I also want to know this…