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SKU: 430103920
Built for a compact .300 Blackout setup, this complete upper pairs Aero Precision’s M4E1 platform with the ATLAS R-ONE handguard for a streamlined, accessory-ready front end. The handguard is designed to keep the profile slim while still leaving room for mounting needs, which suits hunters and shooters who want a tidy setup without giving up flexibility. With the assembled upper and threaded 10-inch barrel configuration, it fits well as a purpose-driven option for short-format builds. The trade-off is straightforward: it emphasizes compactness and modularity rather than a full-size rifle profile.
Complete Upper
Includes Aero Precision's new ATLAS
Slim-profile Handguard
Size and weight in mind
Plenty Real
Estate for attachment needs
Atlas Attachment
System offers a durable, dependable
Maintains Strength
Stability in a streamlined handguard
| Assembled | Yes |
|---|---|
| Attachment System | ATLAS attachment system |
| Barrel Length | 10 in |
| Barrel Threaded | Yes |
| Caliber | 300 Blackout |
| Color | Black |
| Handguard | ATLAS R-ONE Handguard |
| Handguard Length | 9.3 in |
| Profile | slim profile |
| Upper Type | complete upper |
The source data says this complete upper includes Aero Precision’s new ATLAS R-ONE Handguard. It is described as a complete upper assembly, but no additional included components are listed.
It uses Aero Precision’s proprietary ATLAS attachment system on the R-ONE handguard.
Yes. The description says the R-ONE handguard provides plenty of real estate to accommodate attachment needs.
Yes. The ATLAS attachment system is described as maintaining a slim profile while still providing strength and stability.
The product title identifies it as a 300 Blackout complete upper.