This adapter is used to level the top of the slide to a .40 S&W case. This reduces the number of shell tipping when the case tube is full of brass. I did the following: PLA 50% in fill raft (You may not need this) support: 1 mm (in simplify3d) I then hand removed the supports from the "40 s&w" text in simplify3d. It works just fine if you end up snapping off the thin leg on the side. I had to ramp the front of my slide adapter with a modeling knife and sandpaper. This allows some wiggle room and allows the next case to slide up if needed.