A terminal (expert) needs to be hacked to have access. In a small secured area at the back of South Boston Military Checkpoint.(You can only buy from Rowdy after doing some favors for them.) Buy (or steal) parts from Rowdy at the Atom Cats Garage.Behind Proctor Teagan in a cage at The Prydwen is the helmet.Generally you are more likely to find these at Level 28+ Note: Note: Your character level affects your chances of finding parts of this armor.
Below is a list of locations where you can find
