300 Blackout Upper Receivers

Ghost Firearms Vital Complete Upper Receiver .300 Blackout 16in Pistol Length 4150 Light HBAR Barrel 1-8 Twist 11in M-LOK Free Float Hand Guard A2

Ghost Firearms Elite Complete Upper Receiver .300 Blackout 16in Pistol Length 4150 Light HBAR Barrel 1-8 Twist 14in M-LOK Free Float Hand Guard A2

Ghost Firearms Elite Complete Upper Receiver .300 Blackout 16in Pistol 4150 Light HBAR Barrel 1-8 Twist 14in M-LOK Free Float Hand Guard A2 Muzzle

Ghost Firearms Elite Complete Upper Receiver .300 Blackout 16 inch Pistol Length 4150 Light HBAR Barrel 1-8 Twist 14 inch M-LOK Free Float Hand Guard

TacFire 7.5" Unassembled AR 300 Blackout Pistol Build Kit with Lower Parts Kit

TacFire 10.5" Unassembled AR 300 Blackout Pistol Build Kit with Lower Parts Kit

TacFire AR-15 Complete Upper .300 Blackout 10" Barrel Black with Bolt Carrier Group

AR-STONER AR-15 Enhanced Pistol Build Kit with Upper Receiver Assembly 300 AAC Blackout 8" Barrel Pistol Length M-LOK Handguard, Complete Lower Parts Kit with Magpul MOE Furniture Black

AR-STONER AR-15 Enhanced Pistol Build Kit with Upper Receiver Assembly 300 AAC Blackout 10" Barrel Pistol Length M-LOK Handguard, Complete Lower Parts Kit with Magpul MOE Furniture Black

Complete AR15 Upper- Bravo Mount, 300BLK, 13.9" Pin/Weld (16" OAL)

KAK Complete AR15 Upper Receiver - 300 Blackout - 4.75" Barrel - 4" MLOK

DIAMONDBACK DB15 Combo 223 Remington/556NATO 16in 30rd Black Semi-Auto Rifle With Additional 300 Blackout Upper Receiver (DB1721K001)

BCA AR-15 Complete Upper Assembly, 16" 4150 Parkerized M4 Contour Barrel, .300 Blackout, Carbine Length Gas System, 1:7 Twist w/ 15" M-LOK

BattleHawk Armory AR-15 7.5 .300 BLK, 7 MLOK Handguard, Black Complete Upper Receiver w/ BCG & CH

BattleHawk Armory AR-15 10.5 .300 BLK, 10 Mlok Handguard, Black Complete Upper Receiver w/ BCG & CH

BCM 16" 300 BLK 1:7 Tapered Contour Barreled Upper - 15" KeyMod KMR Alpha Rail

NBS 8.5" .300 BLK Pistol M-LOK Upper Assembly

NBS 16" 300 BLK Nitride Carbine M-LOK Upper Assembly

Primary Weapons Systems 300 BLK MK1 MOD 2-M Complete Upper - 9.75"

PSA 16" 300AAC Blackout Pistol-Length 1/7 Nitride 15" Lightweight M-Lok Freedom Rifle Kit w/MBUS Sight Set

Noveske Gen 4 Ghetto Blaster 300BLK 7.94" SBR - Black

Maxim Defense SDX 508 300BLK Integrally Suppressed Upper - 8.5" Black

Maxim Defense MDX 505 PDX 300BLK Mil-Spec Complete Upper - 5.5" Urban Grey

HM Defense HM15P .300 Blackout Pistol Forged Upper HMP15-STFSS-300-F