"E" production pin

This is an unusual production pin. They're usually a round circle with the "E" on a blue background, and red/white/blue "flags" on either side, and no marks identifying the company. This one was made for American locomotive by the Navy Bureau of Ordnance. The company made locomotives and switchers for the war effort, but also made tanks. The back appears to read A.B Co. Utica, NY. A nice unusual pin, with great color! As usual, any other info anyone has is always appreciated.