350 Legend was introduced in 2019 as a fast moving straight-walled cartridge that gives deer hunters in states with caliber/cartridge restrictions a round that delivers optimal power on target with less recoil than other popular hunting calibers like .30-30 or .243 Win. Designed to work with any standard AR15 lower group this 350 Legend RESOLUTE Mk4 Upper Group is just what you need for your next build. Available in six different Cerakote finishes all CMMG Upper Groups come complete with bolt carrier group and ZEROED accessories including: – ZEROED AR15 Polymer Dust Cover – ZEROED AR15 Ambi Charging Handle – ZEROED Muzzle Brake 9mm – Platform: Mk4 – Caliber: .350 Legend – Operating System: Direct Impingement – Barrel Length: 16.1 – Barrel Twist: 1:16 – Barrel Contour: MT – Barrel Material: 4140CM SBN – Muzzle Device: CMMG ZEROED Muzzle Brake – Muzzle Thread: 1/2 x 28 – Gas Port Location: Carbine – Gas Block: 0.750 Non-Adjustable – Upper Receiver: Billet 6061 T6 Aluminum – Hand Guard: CMMG EML15 M-LOK – Finish: Cerakote Standard – Charging Handle: CMMG ZEROED Ambi – Weight: 4.0 lbs – Length: 25