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M4e1 5.56 Assembled Upper Receiver W/M-Lok Atlas S-One Handguard - M4e1 5.56 Assm Uppr 18'''' Rifle 12'''' Atlas S-One Hg Blk
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$529.99
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SKU: 100054451
Overview
Built for shooters who want a complete upper with a streamlined profile, this Aero Precision setup combines the M4E1 threaded assembled upper receiver with the ATLAS S-ONE handguard system. The handguard is designed with size and weight in mind, while the proprietary ATLAS attachment system provides a slim mounting platform with a secure feel. Offered with 12" or 15" M-LOK handguard options and 16" mid-length or 18" rifle barrel configurations, it suits lightweight builds where balance and accessory mounting matter. It is a practical choice for hunters and field-focused rifle owners looking for a ready-to-build upper without unnecessary bulk.
Why Hunters Choose the Aero Precision
Complete Upper
Includes Aero Precision's ATLAS S-ONE
Atlas S-one
Design emphasizes size and weight
Proprietary Atlas
Attachment system offers a durable,
Slim Profile
Helps keep the upper streamlined
Available 12-inch
12-inch or 15-inch M-LOK ATLAS
Key Features
- Complete upper receiver from Aero Precision
- M4E1 threaded assembled upper receiver
- ATLAS S-ONE handguard designed with size and weight in mind
- Proprietary ATLAS attachment system for a slim profile
- Choice of 12-inch or 15-inch M-LOK ATLAS S-ONE handguard
- Available with 16-inch 5.56 mid CMV barrel or 18-inch rifle barrel
Best Used For
- Hunters building a lightweight 5.56 upper with a slim, streamlined handguard setup.
- Shooters wanting an assembled upper with M4E1 receiver and ATLAS S-ONE handguard.
- Users planning a compact, modular rifle build with M-LOK accessory mounting.
- Hunters who prefer a complete upper package rather than sourcing components separately.
Specifications
| Barrel Length | 18" Rifle Barrel |
|---|---|
| Barrel Option | 16" 5.56 Mid CMV Barrel, 18" Rifle Barrel |
| Blade Finish | Blk |
| Caliber | 5.56 |
| Gas Block | Low Profile Gas Block |
| Gas Tube Length | Mid-Length/Rifle Length |
| Handguard | ATLAS S-ONE |
| Handguard Attachment System | ATLAS |
| Handguard Interface | M-LOK |
| Handguard Length | 12" or 15" |
| M4e1 Threaded Assembled Upper Receiver | true |
Pros
- Complete upper includes Aero Precision's ATLAS S-ONE handguard and M4E1 threaded assembled upper receiver.
- ATLAS S-ONE design emphasizes size and weight for a lightweight build.
- Proprietary ATLAS attachment system offers a durable, dependable mounting platform.
- Slim profile helps keep the upper streamlined without adding unnecessary bulk.
- Available with 12-inch or 15-inch M-LOK ATLAS S-ONE handguard options.
- Configured with 5.56 barrel and low profile gas block options in the listing.
Considerations & Trade-offs
- This complete upper is offered in different configurations, so buyers need to confirm whether they want the 12" or 15" ATLAS S-ONE handguard and the 16" mid-length or 18" rifle-length setup before ordering.
- The S-ONE handguard is described as slim and size-conscious, which supports a lightweight build, but that also means less bulk than some shooters may prefer for a more substantial front end.
- The product description does not include detailed specifications for several components, so shoppers who need exact measurements or material details will need to verify those separately.
- Because this is a complete upper, it is best suited to users building around Aero Precision compatibility rather than those looking for a fully assembled rifle package.
Suggested Comparisons
- Complete AR-15 upper receivers
- Lightweight rifle handguard setups
- 5.56 NATO upper assemblies
- M-LOK handguard builds
Suggested Accessories
- M-LOK accessories
- Optic mount
- Backup iron sights
- Sling mount
Frequently Asked Questions
What comes included with this upper receiver assembly?
According to the product data, this complete upper includes Aero Precision’s M4E1 threaded assembled upper receiver and the ATLAS S-ONE handguard. The listed configuration also references a 5.56 barrel, a low profile gas block, and a gas tube, with the exact setup depending on the selected version.
What handguard options are listed for this upper?
The product data lists a choice of 12" or 15" M-LOK ATLAS S-ONE handguard options.
Is this upper intended for a lightweight build?
Yes. The source description says the ATLAS S-ONE handguards are designed with size and weight in mind and are intended as a fit for a lightweight build.
What does the ATLAS attachment system offer?
The description says Aero Precision’s proprietary ATLAS attachment system is a durable and dependable mounting platform that maintains a slim profile while providing strength and stability.
Does the product data specify the exact barrel length and gas system for this upper?
The provided data references both 16" 5.56 Mid CMV Barrel and 18" Rifle Barrel, along with mid-length or rifle-length gas tube depending on the configuration. If you need the exact setup for a specific listing variant, that detail is not fully clear from the source text alone.