I just purchased my first handgun, a glock22 gen 4 law enforcement trade in (comes with night-sights). I have been told by many that they like glocks a lot for many reasons, one being that they are incredibly customizable through after market parts. I have tried to do some research on after market parts for the g22 but have had trouble. Some people seem to say that many parts are interchangeable on glocks but I can't seem to figure out which ones. So, if anyone could explain a little bit about the customization options for a g22 gen 4 it would be incredibly helpful, or any links to websites with explanations would be very helpful as well. I'll take any help I can get, I am trying to become more knowledgeable about these things, I want to get to know my gun perfectly inside and out!