M4E1 Threaded 16" 5.56 Pencil Complete Upper Receiver w/ ATLAS S-ONE Handguard

Aero Precision AR15 Gen 2 Complete Upper, 16" 5.56 Mid Pencil Length Barrel, ATLAS S-ONE Handguard

M4E1 Threaded 16" 5.56 Pencil Complete Upper Receiver w/ ATLAS S-ONE Handguard Product Sku: APPG700207

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This complete upper includes our new ATLAS S-ONE Handguard! The S-ONE line of handguards are designed with size and weight in mind, providing the perfect addition to your lightweight build. Our proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.


  • M4E1 Threaded Assembled Upper Receiver
  • ATLAS S-ONE Handguard of choice
  • 16" 5.56 Mid Pencil CMV 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 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 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
  • Compatible with low profile gas blocks
  • 1.3” Inside diameter
  • 1.5” Outside diameter
  • Compatible with mil-spec AR15 upper receivers and barrels
  • Learn More about our NEW ATLAS S-ONE Hanguards

16" 5.56 Mid Pencil Barrel Features:

  • 5.56 NATO 16" Barrel, 1/7 twist, 4150 CrMoV, QPQ, gas port drilled
  • Pencil Profile w/ .625 gas block journal
  • Mid-length gas system, .0785 gas port
  • M4 Feed Ramp Extension
  • HP and MPI tested
  • Standard A2 flash hider
Made In America? Yes
Platform AR15
Series ATLAS
Caliber 5.56 NATO
Barrel Length 16"
Weight(s) 12" - 47.6 oz / 15" - 48.08 oz
Other No

Customer Reviews

1 Item(s)

Slim and lightweight Review by Lucas
I absolutely love this upper. The ATLAS S-ONE handguard is extremely slim and feels awesome. With the pencil barrel it makes a really lightweight rifle. In my opinion a full length top rail isn't necessary for most people. (Posted on 4/16/2018)

1 Item(s)

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