5.56x45mm NATO Receivers

PRI Mark 12 Mod H AR-15 Complete Upper Receiver 5.56x45mm NATO 16" Barrel 1:7" Twist Black

M4e1-T 223 Wyld Assembled Upper W/Proof Bbl & Mod 4 Handguard - M4e1-T 223 Wylde Assembled Upper 18'''' Heavy Proof Bbl Black

M4e1 Enhanced 5.56 Nato Assembled Upper Receiver For Ar-15 - M4e1 Enhanced 5.56mm Assembled Upper Rcvr For Ar-15 Kodiak

Aero Precision M4E1 Enhanced Assembled AR-15 Upper Receiver No Forward Assist Flat Dark Earth

Mk16 Super Duty Complete Upper Receivers 5.56mm - Mk16 14.5'''' Super Duty Upper Chf Bbl, Ach, Nano Fh/Bcg Odg

Ar-15 Super Duty Nano Complete Upper Receivers 5.56mm - Ar-15 16 Super Duty Nano Complete Upper Receiver Ddc

Mk16 Super Duty Complete Upper Receivers 5.56mm - Mk16 11.5'''' Super Duty Upper Chf Bbl, Ach, Nano Fh/Bcg Blk

FAXON AR-15 X-TRA LITE - RECEIVER SET BRONZE STRIPPED

LMT Defense MRP-L M-LOK Railed Upper 5.56x45mm/.300 AAC Blackout/6.8 SPC no BCG&CH, Black

TROY A4 COMPLETE UPPR 556 16"

Optics Ready AR-15 A3 Pistol U

Stag 15 5.56 16in Tactical Nitride Upper Receivers - Stag 15l Left Hand Tactical Nitride Upper

Mcx-Spear Lt Ar Conversion Kit 5.56 Nato - Mcx-Spear Lt Ar Conversion Kit 5.56 Nato 16'''' Black

East India 5.56x45 Assembled Upper Receiver Starter Kit For Ar15 - East India 5.56x45 Assembled Upper Medium 11.5'''' Bbl W/Rail

BUSHMASTER QRC Upper 5.56 NATO 16" - Black

Colt AR-15 Barreled Upper Receiver 5.56x45mm NATO 11.5" Barrel

LMT MRP-L M-LOK 11.5" Shovelnose Monolithic Upper Receiver

Ar-15/M16 G4 Side Charging Upper Receiver - G4 Side Charging Upper Receiver

Mcr Mag-Only Top Cover

Ar-15 Battle Light Receiver Set 5.56mm

GREY GHOST PRECISION AR-15 Billet Receiver Set 223 Rem/556NATO Black

Mike 15 Gen 2 5.56 Upper Receivers - Gen 2 Complete Upper 12.5'''' Midlength Gas W/A2 Flash Hider

M4e1 Assembled Upper Receiver Threaded 5.56mm Fde - M4e1 5.56 Assembled Upper Rcvr Threaded W/Ar15 Semi-Cut Blk

Sr-15 E3 Mod 2 Upper Receivers M-Lok - Ar-15 Upper Receiver Lpr Mod 2 18'''' Urx