DPM Systems Mechanical Recoil Reduction System for Glock 20, 21, 21SF Gen 1-3

This DPM Systems Mechanical Recoil Reduction 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 system includes one spring plug and three different external springs. The spring plug should Always be Installed when the DPM Recoil Rod and springs are used. The external springs are different in length, the long spring