DPM Colt MK IV 80 Officer .45 ACP Mechanical Recoil Reduction System, Stainless, MS 1911 MK IV

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 1 spring plug and 3 different external springs. The spring plug must always be installed when the DPM Recoil Rod and springs are used.