The TacFire SS-RK300LPK Rifle Kit contains- .300 AAC blackout 16″ barrel;.308 5/8 x 24 TPI spiral fluted flash can w/crusher washer;AR15/.750 micro/low profile gas block/mil-spec/steel; pistol length gas tube w/pin/steel; ultra slim clamp on MLOK free floating handguard; AR15 5.56/.223/.300AAC stripped billet upper receiver w/M4 feed ramps, AR15/.556 Mil-Spec charging handle aluminum w/steel latch; dust cover; AR15 forward assist; AR15 standard receiver end plate; Mil-Spec/commercial castle nut/steel; AR15 pistol buffer tube w/foam; 3 oz buffer w/tube spring; AR15 USA made lower parts kit; AR15 standard A2 style black pistol grip. *Sports South Exclusive.