Stainless steel Glock 19 replacement barrel with a rainbow, oil-slick PVD finish. This is a drop-in replacement component for the Glock 19 pistol and will fit Gen 1-3 slides with no fitting or adjustments. Gen 4-5 slides will need to use a Gen 3 recoil rod with an adapter. It is advisable to lube the inside, top of the slide to allow the barrel to break in properly as tolerances can be tight at first.