This is a model of the steam locomotive, road number 99 5902, for the Harz Narrow Gauge Railways. It is a finely detailed model in heavy metal construction with many separately applied details. The locomotive is driven with two powerful motors, and all driving wheel sets are driven using coupling rods. The doors to the cab and smoke box door can be opened. The finely detailed Mallet design running gear has many details such as complete valve gear and a propulsion mechanism for the lubrication pump.

The prototypical green/black/red paint scheme and lettering is for Era VI, as the locomotive presently looks on the HSB. The locomotive is equipped with a mfx/DCC decoder with many light and sound functions such as headlights, cab lighting, running sounds, a whistle and a bell activated by reed switches, as well as much more.

The running sounds will also work in analogue operation. There is a built-in smoke unit with smoke exhaust synchronized with the wheels, as well as cylinder steam and steam exhaust at the whistle when the latter is activated. There are digitally controlled LGB couplers at both ends, and these couplers can be removed. There are sprung buffers. Length over the buffers 40 cm / 15-3/4".