Aero Precision M4E1 15" Atlas S-ONE M-LOK Complete Upper - 16" - 5.56 NATO

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

Includes:

• M4E1 Threaded Assembled Upper Receiver
• 15" ATLAS S-ONE M-LOK Handguard
• 16" 5.56 HBAR barrel
• Low Profile Gas Block and Mid-Length Gas Tube
• Product comes assembled
• This complete upper does not include BCG or Charging Handle. These products may be selected as add-ons under the FINISH YOUR BUILD tab.

M4E1 Threaded Upper 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 S-ONE Handguard Features:

• Front and rear picatinny rail
• Eliminated center of top rail for weight reduction
• Indexing grooves in 12:00 position for positive grip control
• Quick disconnect sling socket at the 3, 6 and 9 o'clock positions
• 1.3" Inside diameter
• 1.5" Outside diameter
• Compatible with mil-spec AR15 upper receivers and barrels
• MLOK attachment points

16" 5.56 HBAR Barrel

• 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