DPM Soft Mechanical Recoil Reduction System Ruger RXM 4in Barrel. 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. Package Contents: DPM Soft Mechanical Recoil Reduction System What firearm models does the manufacturer say DPM Soft Mechanical Recoil Reduction System is compatible with? The manufacturer says that DPM Soft Mechanical Recoil Reduction System is compatible with Ruger RXM Glock 31 Glock 37 Glock 17 Glock 22DPM MS-RU/6: Soft Mechanical Recoil Reduction System Ruger RXM 4in Barrel