Shipments are delayed until December 30th
These parts are designed to increase efficiency, by allowing you to adjust the volume of air stored inside the engine. They can sometimes reduce FPS.
THE SMALL SIZE REDUCER REPLACES THE O RING IN FRONT OF YOUR SPRING
The medium and large sizes still require the buffer o-ring. The .stl file for these parts is included with every Backdraft Phoenix, so you can print them yourselves!