The author remixed this model.
I made a second side of the glock (by mirroing the first one, so the text is also mirrored) and three pegs which connect the two sides together. The three pegs are named P1, P2 and P3:
P1 (tall, wide) goes into the handle
P2 (small, wide) goes in the middle of the model
P3 (tall, slim) goes into the silencer