Here is the Secondary Regulator. This is simply an air compressor regulator with an internal bleed off for lowering the pressure when needed. It is rated between 0-150psi max. Because Co2 has such a high pressure the primary regulator has to drop the pressure down to a useable psi, otherwise this secondary regulator would blow all of the seals. Take note that there is a gas in and a gas out side and they are both 1/4" NPT, hence the need for the 1/4"x1/8" NPT bushings. Also the "Hose Barb" fitting I am using is a paintball quick disconnect fitting.