There's no missing a GP30's characteristic "hump" which was developed at the GM Automotive Styling Center. As well as creating a more modern appearance, the design was a practical way to house air intakes for the central air system and the dynamic brakes. Bachmann carries on the prototype's innovative history by offering a new DCC sound-equipped model. Bachmann's Sound Value diesel sound package includes prototypical prime mover, 3 air horns, and bell -- all in polyphonic 16-bit sound. This model also features all-wheel drive, operating headlight, and Mark II couplers.