STAINLESS STEEL GUIDE ROD ASSEMBLY - GLOCK 19, 23, 32, 38. STAINLESS STEEL GUIDE ROD ASSEMBLIES ARE A COMPLETE DROP-IN UNIT. FEATURES: •Solid one-piece stainless-steel guide rod. •Precision CNC machined to accept a removable 3/32 Allen head tip. •The ISMI recoil spring is manufactured of certified materials, heat treated for longer life, shot peened for stress relief and finally calibrated to Glock factory specifications 17 lbs. for full-size (17/22/31) and 18 lbs. for compacts (19/23/32). •These combined features make the Lone Wolf Guide Rod Assembly the most durable, longest lasting system available today. Experienced shooters realize plastic guide rods can chip, crack or break resulting in feeding or ejection failures and guide rod flex can contribute to accuracy problems. The Stainless-Steel Guide Rod Assembly addresses all of these issues and will provide you a lifetime of reliable service. You can unscrew and replace with NEW SPRING when you want to. TO USE IN GEN 4 GUNS ORDER ADAPTER AS WELL.