Picked this up for a great deal and figured I would share it in Gun Talk. The M120 was the primary sight for the M139 20mm auto-loading cannon and is 6X magnification. The M139 cannon was used primarily on the M114A1 and M114E1 armored recon carriers, mounted in the commander's cupola. The optics and condition on this one is fantastic and it has serial number 549. This scope is from the Vietnam era during the height of the cold war.
