Production of mechanical and later electrical measurement devices for industry and aircrafts.

Predecessor company of Mechanikai Mérömüszerek Gyára.

Technicians Ferenc  Marx  and Emil Mérei founded company  for voltmeter, thermometer, liquid level meter and spring scale production - Marx és Mérei Tudományos Műszerek Gyára. In the second factory department they produced experimental chemical, physical and electric laboratory measurement devices  what were sold worldwide (Russia, South America, Bulgaria, Spain).

After a few unsuccessful requests in 1911 company received a state grant and they could expand and to build new production area. Factory except special devices for locomotives, warships and Röntgen devices produced electrical ones too, invented by Hertz, Marconi, Tesla.

Since 1918 production of electrical devices was extended, since 1925 by aircraft measurement devices too. In 1930 company was renamed to Marx és Mérei Tudományos-, Elektromos Műszerek és Feszmérők Gyára, in 1942 to Marx és Mérei Tudományos-, Elektromos Műszerek és Feszmérők Gyára- Első Magyar Repülőműszergyár having 2 divisions. In 1943, because the Mérei family was not more involved in management, the aircraft measurement devices production division company was renamed to Marx és Marx Első Magyar Repülőműszergyár.

Production and administration places:

Budapest XIII. Bulcsú u. 7.   
Budapest XIII. Szekszárdi út 19-25.    
Budapest XIII. Frangepán u. 53.   
Budapest V. Wahrmann u. 2. (Ma: XIII. Victor Hugo utca)    
Budapest VII. Éva u. 14. (Ma: Asbóth utca)   
Budapest V. Váci u. 18.

During WW2 factory was involved in measurement device production for Messerschmitt and Hungarian War Ministry, to end of war management tried to move production out of Budapest, but no more influence to battles.

After war a part of employees founded cooperatives Műszaki Munkaközösség és Értékesítő Szövetkezetet , but it was in 1948 nationalized and since 1st August 1949 transformed to Mechanikai Mérőműszerek Gyára.