In January 1939 and order for 1,250 was placed, however this was changed to 800 in May 1939 when the PzKpfw 38(t) production became available.
The driver had a new single piece shutter that helped to better protect him.
There was a new commander's cupola added to the turret roof. There were five vision slits that used a split cover that spread apart when opened.
The second coaxial machine gun was removed from this model forward.
Originally armed with 37 mm (50 were built, but most were later unarmored to the 50 mm) but changed to 50 mm KwK 38 L/42 in July 1940.