This is what 2A Armament says :



2A-Armament is proud to introduce the Aethon billet upper receiver for 2017.  With all the same craftsmanship and weight savings that are trademark to 2A-Armament products the Aethon upper incorporates a forward assist to satisfy personal preference. The Aethon upper styling is designed with interchangeability options in mind and matches perfectly to either a Aethon or Balios Lite Lower.

Aethon Upper Features:

    CNC Machined from U.S.A. sourced 7075-T6 plate aluminum
    Forward Assist
    Bead blasted and hard coat anodized black (Type III, Class2)
    Can be interchanged with third party, Aethon, or Balios Lite Gen 2 lowers
    Weight: (Upper 6.8 oz) Stripped
    Product of the Great State of Idaho, MADE IN THE U.S.A.
    SKU (2A-MCBU-3)


Aethon Upper Receiver

$254.00 Regular Price
$241.30Sale Price