As nice as Power Tube 2200 looked, 3000 and 4000 are even nicer. Rather than an cylinder, both Power Tubes are extruded rounded rectangles, stretching the “Tube” name somewhat. They have the same footprint, though 4000 is half an inch longer than the roughly 3.75” 3000, differences attributable to the sizes of the batteries inside. Rather than separate cables for charging Dock Connector-equipped devices, Power Tube has a pretty ingenious…
