The Battle Arms Development AR-15 Workhorse 16" Upper delivers precision engineering with a 16-inch nitride-finished barrel and M-LOK handguard system for versatile accessory mounting.AR-15 Workhorse 16" Upper Assembly with M-LOK16-inch barrel length with midlength gas system4150 Chrome-Moly Vanadium steel construction1:7 twist rate optimized for various bullet weights5.56 NATO chamber specificationNitride barrel finish for enhanced durabilityA2 barrel profile with 1/2-28 muzzle threadsEngineered by Battle Arms Development's proven expertise in small arms innovation this upper receiver assembly provides reliable performance for tactical sporting and recreational shooting applications.