Top one is an Aero receiver with a BCM keymod rail and a 14.5" Hardened Arms barrel. Comes with a BCM foregrip and an Arisaka light mount. Previous owner tried to change out the handguard with the wrong tools so there are some small cosmetic marks on the receiver. $250
Middle one is a PSA with a 16" chrome lined barrel. It started as an FSB and was converted to free float with a 15" rail from Primary Arms. Comes with a chrome lined BCG, charging handle, and Magpul MBUS sight set. $400
Third one I built myself it's an Aero upper assembly with an unfired chrome lined 16" barrel (sold by Aero under Stag Arms). Comes with an Aero no logo BCG, a Daniel Defense ambidexterous charging handle and a Daniel Defense Omega 7 rail. This is a free float rail not a drop in with rock solid lockup.
𝗧𝗲𝘅𝘁 (𝗰𝗮𝗹𝗹𝘀 𝘄𝗶𝗹𝗹 𝗯𝗲 𝗶𝗴𝗻𝗼𝗿𝗲𝗱) 𝟱𝟭𝟮 𝟵𝟱𝟯 𝟳𝟲𝟵𝟮. Meetup at 𝗔𝗰𝗮𝗱𝗲𝗺𝘆 𝗼𝗻 𝟭𝟬𝟰𝟭𝟰 𝗚𝘂𝗹𝗳 𝗙𝘄𝘆. No shipping and no cashapp, venmo, etc