Rival Arms stainless steel guide rod assembly for Glock 43, 43X, and 48 - CNC-machined 17-4 stainless rod with a tuned recoil spring that replaces the OEM polymer guide rod. Adds muzzle weight where the slim-frame Glocks need it most and drops in with no fitting. The added forend weight reduces felt recoil and helps the front sight track flatter under quick double-taps. Spring rate is matched to the factory carry load and runs reliably with standard or +P 9mm 124 gr defensive ammo. Material: 17-4 stainless steel rod with steel recoil spring Spring rate: factory-matched for 9mm Fit: Glock 43, Glock 43X, Glock 48 Install: drop-in, no fitting required Made by Rival Arms (USA) Break in with 100 rounds of standard 9mm before relying on the new spring for carry duty. Pair with a 3CR slide completion kit if you are also refreshing the recoil channel and firing pin assembly on the same slide. 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.