This AR-15 complete .223 Wylde carbine length upper has a 16" straight fluted heavy barrel with a 416R Stainless Steel finish, and features a 1:8 twist rate, with a carbine length gas system. It includes the new 15" MLOK rail, an M4 flat-top billet upper receiver, a bolt carrier group, a flash hider, and a right side charging (gen 2 ) handle (patent pending). This .223 Wylde upper is compatible with any mil-spec AR-15 lower.