Aero Precision - M4E1 Threaded Complete Upper, 16" 5.56 HBAR Mid-Length Barrel, 15" ATLAS R-One M-LOK Handguard

This complete upper receiver incudes an HBAR profile barrel that is laser marked "HBAR".

Includes:

• M4E1 Threaded Upper Receiver, No Forward Assist
• 15" ATLAS R-ONE Handguard
• 16" 5.56 HBAR barrel
• Low Profile Gas Block and Mid-Length Gas Tube
• Port Door Assembly
• A2 Flash Hider
• Does NOT include BCG and Charging Handle

M4E1 Threaded Upper Receiver Features:

• New enhanced forging that gives the upper receiver a "billet look"
• New picatinny profile that blends seamlessly with our Enhanced Series Handguards
• M4 Feedramps
• .250 takedown pin holes
• Laser engraved T-marks
• Includes port door and forward assist installed

ATLAS R-One Handguard Features:

• Full top picatinny rail for optional attachments
• Quick disconnect sling socket at the 3, 6 and 9 o'clock positions
• Compatible with low profile gas blocks
• 1.3” Inside diameter
• 1.5” Outside diameter
• Compatible with mil-spec AR15 upper receivers and barrels

16" 5.56 HBAR Mid-length Barrel Features:

• 5.56 Nato 16" Barrel, 1/7 twist, 4150 CrMoV, QPQ, gas port drilled
• .750 gas block journal
• Mid-Length Gas System
• M4 Feed Ramp Extension
• HP and MPI tested
• Standard A2 flash hider