Anderson Manufacturing lower (standard not PCC), AT3 slick side upper, mil-spec LPK, mil-spec upper parts kit (charging handle, dust cover, forward assist), 9mm BCG (17oz), standard buffer spring, pistol buffer tube (with spacer inside), 3.5oz buffer, 5" barrel, 5" flash can, 4" free float handguard, Endomag converted P-mag (30 round).
Less than 10 rounds through it; just to make sure everything operated correctly. 
Could easily be changed to another caliber with new BCG & barrel.