DPM Mechanical Recoil Reduction System Iwi Masada Slim 3.4 Barrel Long. Also it is compatible for low power ammunition. The system works due to the multi spring intricate rod (3 springs) and controls the functionality of the gun. The third spring which is contained within the rod controls the movement of the slide so it never rams on the frame. Package Contents: DPM Mechanical Recoil Reduction System What firearm models does the manufacturer say DPM Mechanical Recoil Reduction System is compatible with? The manufacturer says that DPM Mechanical Recoil Reduction System is compatible with Ruger RXM Glock 20 Smith & Wesson M&P Compact IWI Masada Canik TTI Combat SIG Sauer P365 Springfield Armory TRP OperatorDPM MS-JE/6: Mechanical Recoil Reduction System Iwi Masada Slim 3.4 Barrel Long