Cross Armory 3 Pin Set enhances geometry for improved ergonomics with 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 the holster. Fits Glock 17/19/20/21/22/23/24/26/27/29/30/31/32/33/34/35/38/39 Gen1-3. *Note- Does not fit 42/43/43x.