the wall of the Base, its only one part from mid copper strut to mid copper strut.
the Gate is here: http://planet-explorers-isos.com/planet-explorers/iso-details-military-base-gate-704.html
the Wall Corner (+ tower) is here: http://planet-explorers-isos.com/planet-explorers/iso-details-military-base-corner-tower-702.html