It was the second biggest Romanian pre-war aircraft manufacturer, after Industria Aeronautică Română (IAR).

[1] The Societatea Pentru Exploatări Tehnice was established in Bucharest in 1923 by Grigore Zamfirescu as a general machinery manufacturing plant.

It soon specialised in building aircraft to its founder's design, supplying the Romanian Air Force with trainers during the mid-1930s.

[1] At the peak of aircraft production, Zamfirescu changed the company's name to Fabrica de Avioane SET.

This venture was to have been called "Industria Nationala Aeronautica" ("National Aeronautical Industry"), but it failed to materialise when the Second World War intervened.