[citation needed] During the 1990s, Mastretta focused on microbus (Mexico City metropolitan minibuses) body chassis design and engineering, as well as that of urban buses.

For this prototype, the engine delivered 44 bhp (33 kW; 45 PS) and reached a top speed of 127 km/h (79 mph).

A few hand-made units were exported to Germany, Japan and the USA, where the kit-car marketing was attractive for many collectors at the time; those that remain in Mexico are owned by Mastretta.

Automóvil Panamericano car magazine's February 1998 annual edition of Modelos (Models, a special catalogue with information about every commercial model on Earth and since that year, a few pages dedicated to kit-car makers) featured a paragraph on the Unediseño Mastretta.

With a proposed production of 200 MXT autos per year, Mastretta's Tecnoidea calls itself Mexico's only automaker.