The main battle tank 3 programme was an experimental development from the 1970s, in which an advanced casemate tank concept with two cannons was tested instead of the turret tank concept. The experimental vehicles were, for example, the VT1-1 and VT1-2. The variant here was another design that was developed in parallel to the Leopard 2 AV or the Leopard 2 flat turret concept and, apart from the same chassis components, drive and RH120 gun, also had a remote-controlled MG3 mount (remote-controlled weapon station).