The Pip-Buck 3500 is like any standard Pip-Buck 3000 in it basic functions. But it was more based of the Pip-Buck 3000 delta model, which was the best version of the Pip-Buck at the time.  
While the Pip-Buck 3500 is based off Pip-Buck 3000 delta, it is upgrade over it with more features and a bit tougher over it previous versions.
 
The Pip-Buck 3500 new features are Improved radio selection, Junk tab in the item section, improved E.F.S, and can enter a terminal from a few feet. While the standard Pip-Buck 3500 colors is the default Pip-Buck 3000 model. This specific one was custom made for a pony which was a military pony that went to Stable 23 in the Detrot area. Strangely there is a extra part inside this custom Pip-Buck 3500 that isn’t in any other Pip-Buck 3500. Many many years later this specific Pip-Buck 3500 will be Comet Pip-Buck and the reason why she had to leave her stable and enter the equestrian wasteland.