These O-rings go around the Hex Drive Bushings and work together with the Grip Screw O-rings to give the best possible mounting for your grips. The system prevents the grips from shifting during discharge. Very effective for preventing grip screws from loosening.
By design, 1911 grips have holes that are larger than the bushings to allow for manufacturing tolerance. When grip screws are installed everything tightens up. Or does it? During recoil the oversize holes allow the grips to shift slightly on the frame, the very place you grasp the weapon…a place where you don’t want anything to shift.