mhmcasey wrote an answer about MHM Incline 18 Backpack - 1098cu in on August 6, 2013
Actually, the Incline is hydration compatible. There is a designated sleeve against the backpanel for a bladder as well as a clip to hang it from. As far as a port hole, we designed the pack so that you can unzip the backpanel fabric and run the tube through the vent holes on the top of the pack. So to correctly answer your question, yes, the pack is quite hydration compatible!