RA Tech pioneered the NPAS (Negative Pressure Adjustment System) technology and while it premiered for the WA / G&P gas blowback M4 system it has since become available for many other GBB weapons.
This valve is for installation into the KSC / KWA gas blowback MP7 SMG and other gas blowbacks that use the System 7 technology. It allows more reliable shot-to-shot power (FPS) and allows the adjustment of the gas flow to reduce or increase the power (FPS) either greatly below or slightly above the factory performance.