Drops on Glock 23 Gen 1, Gen 2, and Gen 3 frames in .40 S&W. Shop-assembled by 3CR Tactical on a Remsport bullnose nitride blank - Gen 5 aesthetics on Gen 3 geometry. Barrel, sights, and internals installed and tested. Finish: Matte black nitride on slide and barrel. Uniform, low-glare, holster-friendly. Specs Caliber: .40 S&W Host frames: Glock 23 Gen 1, Gen 2, Gen 3 (NOT Gen 4 or Gen 5) Profile: bullnose front, Gen 5-style aesthetic Optic cut: RMR with recoil bosses - Trijicon RMR/SRO, Holosun 507C/407C, Sig Romeo1 Pro Optic screws: 6-32 x 7/16" - match to your optic manufacturer kit Barrel: black nitride, factory-length Sights: tall polymer suppressor-height Internals: 3CR extractor, firing pin assembly, plunger, recoil rod Before You Run It Lubricate the rails before first install and run 200 rounds to seat the new components. Confirm Gen 1-3 frame and RMR-with-recoil-bosses footprint before mounting an optic. DISCLAIMER: "GLOCK" is a federally registered trademark of GLOCK, Inc. and is one of many trademarks owned by GLOCK, Inc. and GLOCK Ges.m.b.H. Neither 3CR Tactical nor this site are affiliated in any manner with, or otherwise endorsed by, GLOCK, Inc. or GLOCK Ges.m.b.H. The use of "GLOCK" on this page is merely to advertise the sale of GLOCK pistols, parts, or components. For additional genuine GLOCK, Inc. and GLOCK Ges.m.b.H products and parts visit www.glock.com.