The HP OfficeJet Pro 8600 is a solidly constructed MFP with plenty of features to like.
The purchase price is also reasonably attractive.
The other two are the 8600 Plus and 8600 Premium.

That last one is the most complete model but also the most expensive to buy.
Take a look at its display, for example.
Though smaller and has fewer touch buttons, it provides the same onscreen interface as those of its siblings.

The printer has no manual feed slot.
Its paper handling system includes a 250-sheet paper tray and a 35-sheet automatic document feeder (ADF).
The former is at the very bottom of the printer, well hidden below the 150-sheet output tray.

The latter is typically positioned on the top of the printer.
Being the cheapest out of the three models, the HP OfficeJet Pro 8600s print speed is slower.
32 ppm at draft quality and 5 ppm at best quality for black pages.
The ones included in the other two models can print, copy, and scan double-sided pages.
Fortunately, wireless connectivity is not in the list of missing features in the HP OfficeJet Pro 8600.
This is impressive because there arent many inkjet printer can achieve the same feat.
This is why printing at draft quality is preferable for internal documents.