 During the Siege of Leningrad, LIFMO continued to operate a military repair facility for the Leningrad front.It was established in the first days of war and it fabricated test and measurement instruments for army and navy units.During the Siege, the facility developed improved optical sights, fixed artillery binoculars, gun panoramas, anti-aircraft sighting telescopes, periscopes, machined “cups” for anti-aircraft shells and parts for land and sea mines.