The Balios-lite Gen 2 billet upper and lower receivers were designed with weight savings as the prime objective. Balios-lite Gen 2 is perfect for those who participate in 3-gun” hunting” or any other shooting activity where weight is a concern. This upper receiver will fit any of 2A Armament’s AR15 lowers perfectly (Balios” Balios-lite” Balios-lite Gen 2″ or Aethon) and will also fit any standard Mil-spec lower from other vendors. The tapered transition under the charging handle prevents associated wear patterns from damaging the finish. We have eliminated the forward assist” and retained the port door cover.