Rap4 Paintball Quick Drop Out Changer 12g Co2 Adapter - Black This upgraded quick changer takes only a few turns to remove and reload a CO2 cartridge. Change those 12 grams faster with this kit. Simply turn the knob the used 12 gram drops out and replace with a new 12 gram in seconds. The 12g cylinder can put out about 20-30 charges and about 15-20 shots for paintball guns. The cartridge is pierced and the CO2 flows into the marker. All Metal Construction.