MAC MAC 5K 9mm Luger 30+1, 5.8" Black Steel Threaded Barrel, Black Phosphate Receiver, Black Pistol Grip The definitive firearm of the MAC era is back and better than ever. The firearm is compatible with both MAC & HK branded furniture made for the MP5. Mac 5K tactical pistol features a roller delayed blowback action; lacquer paint over phosphate; hooded front sight, Diopter rear sight; Tri-Lug threaded muzzle; paddle mag release. Takes standard MP5 magazines. Includes two 30rd magazines, Tri-Lug flash hider, cleaning kit and sling.