Quick Change 12g CO2 Adapter w/88g or 90g Capsule Threads for SIG SAUER MCX/MPX | eBay
M16x1.5 Thread Quick Change 12g CO2 Valve Cartridge Adapter Machinery Parts - Machinery Parts Other Accessories - 1 x M16X1.5 Quick Change 12g CO2 Cartridge Adapter - Amazon.com