Master Model from Poland specializes on brass and resin drop-in replacement parts. In this case there are 4 parts: two barrels and two flash hiders for the Flak 18 used in Ju-87G, but also seen in Bf-110, Ju-88 and other airplanes.
The turned brass parts mean that no mold line is present and that alone is enough of a reason to consider upgrading your kit. Another reason is the beautiful perforated flash hiders and the hollow gun barrel end, which adds realism to the airplane weaponry.
Assembly is straightforward and simple. First you superglue the flash hider to the gun barrel. Then you remove the plastic gun from the plastic part and make a small hole (1 mm in diameter) to mount the brass gun barrel.
I would personally leave the barrel off the model until the very end. Not only that means less masking (for painting), it also ensures the barrel won’t get knocked off the model during handling.