Numbers 1-50 were built by Robert Stephenson & Company and numbers 155-164 were built by Beyer, Peacock & Company.

In 1859, following the Second Italian War of Independence, the LVCI network was divided into a Lombard part (Lombardy was annexed to the Kingdom of Sardinia) and a Venetian part (Veneto remained a possession of the Austrian Empire).

In 1865, when the Società per le strade ferrate dell'Alta Italia (SFAI) was established, the Lombard machines were taken into the stock of this company and became SFAI 31-65.

The following year, after the Third Italian War of Independence, which resulted in the annexation of the Veneto region to the Kingdom of Italy, the 25 Veneto machines also came into SFAI stock and were numbered SFAI 66-90.

The SFAI scrapped 10 machines in 1874, and rebuilt another 10 with 2-4-0 wheel arrangement, giving rise to the 301-311 series.