Agency Arms Mid Line Barrel focuses on additional machining enhancements and appearance. It is constructed of 416R stainless steel with pulled broached rifling and 8 Gear flutes machined around the circumference of the barrel. Caliber information is machined on the rear, while a large Agency "A" on top and "Agency" are machined on the port side of the lockup. This threaded model is compatible with Glock 17 with a black DLC (diamond-like carbon coating) finish and 1/2x28 threads. Included is a thread protector.