Awesome knife. Make sure that you can legally carry it in your home State though. Check your State knife laws.
I bought one (LOVE IT!) and can legally own/collect/possess it but, it is "prohibited" on the Pennsylvania Prohibited Offensive Weapons list "out on the street" because....it is a knuckle knife.
If Brass Knuckles are prohibited in your respective State then the AA will be also. And if that isn't sad enough it is also technically classed as a "DAGGER" (for obvious reasons)
So....in PA. I am perfectly legal to carry a concealed firearm BUT, I would be "up the creek without a paddle" out in the woods with the AA if some person of authority wanted to pursue the issue.
State knife laws are mostly written by egg headed morons who know absolutely nothing about knives.