The Tatra KTNF6 is a modernized tram, type KT4, rebuilt with a central low-floor segment. These types of tram cars are used in Cottbus, in Brandenburg City and Schöneiche-Rüdersdorf, Germany, and in Tallinn, Estonia (as KT6TM). Another similar variant of KT4 is KTNF8 (also called KT4NF), which is used in Gera (Germany).[4]
These trams have new interiors, chairs, doors and middle sections with low floors.
The breakdown of the type designation is as follows:[5]