The extra weight of our stainless steel and tungsten guide rods for your Mini-Glock helps the gun shoot better and feel better. You'll be able to shoot faster and more accurately while reducing recoil and muzzle jump. It's a drop-in part with the dual springs included and captured on the rod. And, now you can select the spring weight that is best for you. The Glock is a wonderful gun...we all know that. But some of the parts should be changed to improve performance. This part is more than 50% heavier than the factory plastic part which will help you shoot the gun faster and more accurately because it reduces recoil and muzzle flip.