DPM FN 509 LS Edge 5'in Barrel Adjustable Mechanical Recoil Reduction System. This high-end tech system works due to the multi-spring intricate rod (2 springs) in combination with the 4 external springs that work as buffer and controls the functionality of the pistol. The long springs set is softer than the standard springs. 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 FN 509 LS Edge 5in Barrel Adjustable Mechanical Recoil Reduction System: Manufacturer: DPM Fabric/Material: Spring Steel Gun Make: FN Herstal Gun Model: FN 509 LS Edge Features of DPM FN 509 LS Edge 5in Barrel Adjustable 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 FN 509 LS Edge 5in Barrel Adjustable Mechanical Recoil Reduction System What firearm models does the manufacturer say DPM FN 509 LS Edge 5in Barrel Adjustable Mechanical Recoil Reduction System is compatible with? The manufacturer suggests that DPM FN 509 LS Edge 5in Barrel Adjustable Mechanical Recoil Reduction System is compatible with FN 509 LS EdgeDPM MS-FNH/8: FN 509 LS Edge 5'in Barrel Adjustable Mechanical Recoil Reduction System