5.56x45mm NATO Upper Receivers

M4-L89 5.56x45 Nato Assembled Upper Receiver - M4-L89 5.56x45 Nato 10.5'''' Bbl 9.75'''' L89 Rail W/Nox9

M4-L89 5.56x45 Nato Assembled Upper Receiver - M4-L89 5.56x45 Nato 14.5''''bbl 13.75'''' L89 Rail W/Nox9

Heckler & Koch HK MR556 Upper Receiver Kit w/Bolt, Buffer Spring, M-LOK, & Barrel Assembly 81000584

HK USA MR556-A1 Match 5.56 Upper Receiver Kit

ANDERSON Upper 20" w/NO BCG or Charging Handle 5.56/223

Anderson Manufacturing 16 Barrel 5.56/.223 Upper w/Front Sight Base

BUSHMASTER M4 Type Patrolman A4 Upper 5.56 NATO 16" Black

BUSHMASTER Bravo Zulu A4 Upper 5.56 NATO 16" - Black

FOSTECH RECON 10.5" 5.56 BLK

Dark Storm Industries DS-15 Complete Upper 16" Lightning 5.56 Threaded Black 5.56

M16 R0901 5.56 Complete Upper Receiver Groups - M16 Upper Group 20in M16 Handguard Stripped

M16 R0901 5.56 Complete Upper Receiver Groups - M16 Upper Group 20in Moe Stripped

M4 5.56 Upper Receiver Groups - M4 Le6933 Upper Group 11.5'''' Stripped

M4 5.56 Upper Receiver Groups - M4 Le6921 Upper Group 14.5in Stripped

Colt LE6933EPRII-PRO 5.56mm 11.5" Bbl Matte Black Metal MBUS Sights HuxWerks Muzzle Device Upper Receiver Conversion Kit LE6933-EPRII-PRO-HUX-CK

Colt LE6933EPRII-SF3-CK 5.56mm 11.5" Bbl Matte Black MBUS Sights Surefire Muzzle Device Upper Receiver Conversion Kit LE6933-EPRII-SF3-CK

Colt Monolithic AR-15 Pistol Complete Upper Receiver 5.56x45mm NATO 14.5" Barrel

PRI Mark 12 Mod 0 AR-15 Complete Upper Receiver 5.56x45mm NATO 18" Barrel 1:8" Twist Flat Dark Earth

FOSTECH STRYKER 10.5" 5.56 BLK

Brn 16a2 Upper Receiver - Brn-16a2 5.56x45 Nato 20'''' Bbl Upper Receiver

Brn-16a4 Complete Upper Receiver - Brn-16a4 5.56x45 Nato 20'''' Bbl Upper Receiver

Brn-773 Upper Receiver - Brn 733 C7 5.56 Upper Receiver, 11.5'''' 1-7 Twist Black

Brn-601(R) Retro Complete Upper Receiver - Brn-601 5.56mm 20'''' Bbl Upper Receiver

Brn-4(R) Complete Upper Receivers - Brn-4 5.56mm 16'''' Heavy Bbl Complete Upper W/13.5'''' Handguard