The Glockstore Heavy Tungsten Guide Rod is the most popular upgrade for Glock owners worldwide. It's an easy, drop in part that is 5x heavier than the factory plastic part and 3x heavier than the stainless steel guide rod. You'll find that you will shoot faster and more accurately with the Tungsten Guide Rod installed. The increased weight of the rod helps reduce felt-recoil and muzzle flip enabling you to keep your sights aligned and shoot tighter groups in faster times. A high quality, American made spring included and captured on the Tungsten Guide Rod as pictured. You simply drop it in and replace the factory plastic rod in seconds! NoteGlockstore Heavy Tungsten Guide Rods weigh roughly 52-58 grams as compared to stock guide rods which weigh between 12-16 grams. DISCLAIMER: This product is not manufactured, authorized, endorsed, or warranted by GLOCK. GLOCK does not warrant or represent that this product is compatible with GLOCK pistols.