This Zaffiri Precision Complete Upper takes the time tested ZPS.1 slide and blended it with the Blowhole Compensator allowing you to manage that unruly gas. Gain the flat shooting features of a compensated setup without the threaded barrel. The single billet 17-4 stainless steel slides are made with tight tolerances that allow an increase in accuracy and performance. These are among the best aftermarket slides available for Glock. This slide is pre-cut and pre-coated.