The True Precision Glock 17 Threaded Barrel delivers precision engineering with nitride finish for enhanced durability and 1/2x28 threading for suppressor compatibility.True Precision Threaded Barrel for Glock 17Fits Glock 17 Gen 1-4 Models Only9mm Luger caliber1/2x28 threaded for suppressor/muzzle device attachmentBlack nitride finish for corrosion resistance1:10 Left Hand Twist Rifling for accuracyEngineered and manufactured in the USAPerfect for shooters seeking enhanced accuracy and suppressor compatibility this barrel combines True Precision's commitment to quality with precise American manufacturing standards.