Pearce Grip Frame Insert, Fits Glock, Except 26/27, Black PGGFI This unit installs in the bottom rear cavity of the frame utilizing the lanyard hole for retention. Fits M17" 18" 19" 20" 21" 22" 23" 24" 31" 32" 34" 35" 37" and 38. This product will not fit any SF (Short Frame) or any Generation 4 or 5 frames.