Threaded End Cap adapters for use with the GM-45 and Blackside suppressors. These allow the use of the suppressor on fixed barreled weapons. Notes: Thread Use:1/2-28: (9mm Carbines)9/16-24: (for use with .40 S&W) 5/8-24: (300 BLK) 1/2-36: (9mm Carbines Colt, RRA, Bushmaster) 0.578-28: (45 ACP Carbines) M13.5x1LH: (9mm Carbines/ Sub Guns)M16x1LH (45 ACP Carbines, KRISS)