Ballistic Advantage Premium Series, 9MM, 4.5 Threaded Barrel, 1/2x28, Spiral Fluting, Glock 19 Gen 3-5, Copper BAPSG195T3R Designed to meet the demands of the most discerning shooters" the Ballistic Advantage pistol barrels are the latest platform addition to their Premium Series. Known for its strength" toughness" and good ductility" their pistol barrels feature a hardened 416R stainless steel material for absolute durability and corrosion resistance. Each barrel is honed" lapped" and tumbled to ensure it is free of any imperfection and ready for flawless performance" with no break-in period required. All barrels are held to less than .0001 deviation of the bore" reaching better than factory tolerance for optimum reliability and accuracy.