DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System 9x19 40S&W. This system works due to the multi spring intricate rod (three springs) and controls the functionality of the pistol. The third spring which is contained within the rod controls the movement of the slide so it never rams on the frame. The washer must always be installed when the DPM Recoil Rod and springs are used. As lead the evolution of recoil reduction technology products may change versions (new design with different springs with or without plugs washers etc.) without any prior notice. Specifications for DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System: Manufacturer: DPM Fabric/Material: Spring Steel Gun Make: Steyr Gun Model: Steyr M-A2 Steyr M-A1 Features of DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System Faster follow up shots Improved firing speed Slide and Frame Protection Elimination of jams Significant recoil reduction Better double-tap concentration Better control and greater accuracy Package Contents: DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System What firearm models does the manufacturer say DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System is compatible with? The manufacturer says that DPM Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System is compatible with Steyr M-A1 Steyr M-A2DPM MS-ST/1: Steyr M-A1/ A2 Full Size Mechanical Recoil Reduction System 9x19 40S&W