Requires a high quality printer with tuned seams, support, etc. Both should be printed in an orientation that the cylinders are printed accurately. Do not dry fire, or use the blaster without it being fully assembled as the plunger relies on the body of the blaster for support. This will not work with the stock piece that keeps the blaster from breaking open to reload, so I would test to make sure the cylinder works well before you make any permanent changes to your blaster. I used some CA glue to glue the two pieces together.