Softronic Transmontana No. 91 53 0480 017-9. Side corridor. For reasons of space, the transformer is installed above the ground, and this meant having two side corridors as it's known from many much older locomotive classes (such as the Electroputere six-axle locomotives, distant ancestors of the Transmontana series). InnoTrans, Berlin, 2014-09-23 to 26.