Back patches

Why don't you Google it and try something online. I'm on Google right not looking it up. I mainly see ones for jean jackets aswell. Well, let me rephrase that, I mainly see them on jean jackets. I actually helped my friend put one on his jean jacket. It looked so badass. Does it matter though? I always thought patches were patches.
 
Are you sure there are different patches for different jacket materials? The people I have known have just bought patches and attached them to whatever material they had. I dont see the big thing. For denim they can be sewed on and for leather you glue them to the material. I always thought the patches were the same though.