Cross Armory CRG4PSRD: Cross Armory Dimpled Pin Set for the Glock Gen 4 handguns. Features enhanced geometry for improved ergonomics and decreased install time. This product is precision machined, not cast, from 4140 Ordnance steel. It is then surface treated for improved finish and corrosion resistance. Does not interfere with any holster. Designed specifically for Gen 4 models, including additional longer backstrap pin models. Fits Glock Gen 4 17, 19, 20, 21, 22, 23, 26, 27, 29, 30, 31, 32, 33, 34, 35, 40, 41.