You can find the True Precision Threaded Barrel for Glock 19/19X/45 Gen1-5 Black DLC here.

True Precision barrels are easy to install with a drop-in design and have an advanced proprietary broach cut design specifically engineered for increased accuracy potential. An improved overall fit over the OEM barrel with added chamfers, improved radius cuts, and other additions. The broach cut 6 groove rifling allows for all ammo types to be used safely, including cast lead. The barrel has 1/2x28 threads with included thread protector, 1/10RH twist rifling and SAAMI spec chamber. Lifetime performance manufacturer warranty for function. Made 100% in the USA with USA sourced certified 416R stainless steel.

Firearm: Glock 19/19X/45 Gen 1 - Gen 5
Caliber: 9mm
Color: Black DLC
Suppressor Threads: 1/2x28