Built by Aero Precision, Featuring Premium Superlative Arms Clean Running Piston Components. The muzzle device is pinned and welded to achieve legal NON-SBR 16.1" length.
The M4E1 Superlative Arms Complete Upper Receiver Groups, built by Aero Precision, feature the well-regarded Superlative Arms Piston Kit. This Upper Receiver was spec’ed out by Brownells and Aero Precision to integrate seamlessly with the Superlative Arms Kit. Perfect for a Suppressor host or for those who simply don’t like cleaning the chamber area of your AR-15, these Upper Receivers vent hot gasses and debris at the gas block, not in the receiver like a traditional gas impingement AR. The adjustable Superlative Arms Gas Block allows you to fine tune your gas setting and can be easily adjusted through the front of the handguard. The gas piston can easily be removed through the front of the handguard as well, for easy maintenance. The M4E1 is Aero Precision’s Enhanced Upper, that allows for rigid interface with the MLOK Enhanced Handuard. The M4E1 Handguard offers a full length Picatinny top rail, machined-in QD sockets and MLOK accessory slots at 3, 6 and 9 o-clock. Bolt carrier has a slick DLC (diamond like coating) finish and the bolt has a hard & slick nitride finish. The bolt itself is magnetic particle inspected for microscopic defects. Uppers are available with a 14.5 inch 5.56x45 barrel, with a nitride finish.