It might be too big for a dock box
StephenWe saw these stand up, roll around room AC systems at several places (from Pep Boys Auto to Brands Mart). Considering its winter, I would doubt Target has them on display. Our unit, made by Hier is about 34 inches high, 14-15 inches square. The 4-5 inch diameter hose connects to the rear and is the accordian collapseable type that entends out to a good 6-8 feet or so, thus allowing flexibility to get to a port for exhausting the heat. The 9,000 btu model we have puts out pretty cold air that is sufficient to keep the cabin cool. We stand it up in our quarter berth and vent out the quarter berth port. We had a few weeks of intense heat here and the unit could not keep up with the heat build up below. Needless to say, we all jumped in the lake to stay cool!! We weighed out the options on standard window units and the cruise and carry models and came to the conclusion that this was the easiest to handle and store. It might be to big for your deck box and its a bit heavy to move back and forth. It stores well for us while sailing as we bungee it against the entrance ladder.Bob