I have a G19 2-pin model . I have read that some people look for these over the newer 3 pin models . Why is this and is there any difference in reliability ? I think that Glock made the 3 pins for the bigger bores and then the 9mm just got put into the mix to make manufacturing easier . Is this right ? Mine is a 2 pin G19 with the finger grooves and light rail . What year do you guyys think it is ? I bought it new but forget what year . I didnt realize that Glock made 2 pins with the finger grooves and rail . Now that I am detail stripping my Glocks , I realized that it had 2 pins instead of 3 .