With MK23s one of the preferred pistol these years, various manufacturers got their own to sell. Mach Sakai takes a look at one from KSC and it is a CO2 powered one... "Review on T-REX, a military handgun revived as a CO2 blowback Release date 2023/3/29. Equipped with a CO2 power unit "System Zero" that can be enjoyed all year round. Also pay attention to the mechanical operation feeling. Adopted the biggest big bore cylinder (inner diameter 15.5mm) of KSC pistol."