TACKLE TWILL NUMBERS

The Authentic jersey has up to 3 layers of tackle twill material, depending on the team.
Tackle twill, or applique, involves the sewing down of material, usually a nylon twill, to clothing. Multiple layers are glued together to make them flat.
Teams like the Patriots and Bucs have 3 layers, this make it easy to tell a fake as you can see the numbers and stitching well.
Others like the Steelers and Giants only have a single layer and this can be very difficult to see from a small picture on ebay.
Fakes use an inferior material for the numbers and they aren't glued down so they bubble.

These numbers are prime examples of fakes, notice how bubbly they are and how poor the stitches are.
The cheaper material make's the numbers look shiny too.

Here are the genuine numbers, you can see they are flat,with no bubbles and have a matt finish.
A couple of teams, Raiders, Seahawks and Cardinals use a ribbed dazzle twill which is ridged and gives it a slight shine to it, but nowhere as shiny as the fakes.