I went to
www.parkergun.org, and was told that the number 3 above the serial number on the water table was grade 3, or grade D. He said what I thought was an "A" behind the trigger guard is actually an "N", which just means number. Does this sound right? Looking at the gun again, I can see where it might be an "N". The letter is engraved kind of fancy and there is some wear there.