US-based company producing a rather cool model of a Renaissance tank based on Da Vinci's designs, mastered by Tobsen.
2. Tobsen77 Miniaturen
If round conical tanks aren't your thing and you think Leonardo was a nutcase, there is also this excellent resin model sculpten by Tobsen.
Italian company that, among other things, has a historical range that includes a carrioco (warwagon) and a bellwagon (the latter making a nice alternative war altor base).