The AM-15 Optic Ready 5.56 16? - M4 is our Entry Level Rifle. With manufacturing all our parts here at Anderson Manufacturing we are able to offer you Affordable American Made Quality for Less! The Optic Ready Rifle is a high quality rifle for a low cost. Just add an optic of your choice and you are ready to take on range day!Specifications: Weight: 9.00 Federal firearm license required for purchase: yes Lower receiver material: forged 7075 t6 aluminum Upper receiver material: forged 7075 t6 aluminum Trigger guard: open trigger Receiver finish: type 3 hard anodized black Rf-85 treated: non-treated Bolt carrier finish: nitride Bolt carrier material: 8620 steel Bolt finish: nitride Bolt material: 9310 steel Barrel material: 4150 chrome moly vanadium Barrel length: 16 inch Barrel finish: nitride Barrel contour: m4 contour Twist rate: 1:8 Fluting: none Gas system length: carbine length Gas system type: high rise Gas block diameter: .750 inch Charging handle: standard charging handle Bolt carrier group: standard m16 profile Handguard: a2 plastic hand guard Hand guard type: a2 style Hand guard length: carbine length Pistol grip: a2 style Thread pattern: 1/2 - 28 Muzzle device: a2 flash hider Buffer tube: 6 position buffer tube Butt stock: 6 position carbine butt stock Product upc: 784672476874 Unit of measure: ea Country of manufacture: United States