Heizer’s PKO 45 is a compact, all-metal, internal-hammer-fired, semi-automatic .45 ACP pistol that measures only eight-tenths of an inch wide. Manufactured by aerospace fabricator Heizer Defense, makers of the similarly slim PAK1, PAR1 and PS1 single-shots, the PKO 45 is unconventional, with a fixed, ported, 2.75" barrel whose axis lies below that of the guide rod assembly and below much of the slide’s mass to enhance accuracy and reduce muzzle flip, respectively. Magazine capacity is five rounds in the flush-fit style or seven for the extended style. The PKO 45 features a manual, bilateral, frame-mounted safety and frontstrap-mounted grip safety along with slide-stop and magazine buttons. Both front and rear sights are dovetailed to the slide. The aluminum-frame PKO 45 weighs approximately 25 ozs. and is available in Ghost Grey, Copperhead and Tactical Black. A titanium-frame variant is in the works. heizerdefense.com