This WE-Tech magazine is designed for 1911 Hi-Capa 4.3 CO2 pistols, which are designed to use CO2 and not other propellants like propane. Therefore, this magazine is only compatible with 12g CO2 cartridges, which must be bought separately. The baseplate can slide open to accept the cartridge.
The metal frame is strong enough to withstand a users constant running, colliding, and magazine impact. However, its still light enough for easy carrying, as shooters often pack several for extra ammunition.
The total magazine capacity is 28 rounds, which is standard for WE-Techs 4.3 Hi-Capa line. That will let you take out many enemies on the battlefield.