AMTROL has been manufacturing Reverse Osmosis Water Storage Tanks for over 4 decades. Not only have we been doing it longer than anyone else, we actually invented the technology behind RO tanks. Our proven technology, vast experience and countless other qualities are what place AMTROL high above other manufacturers with their look-alike tanks. Remember, looks can be deceiving. And in the end, you always get what you pay for. Fully enclosed polypropylene and butyl water reservoir ensures water purity, and there's less rubber/water contact than with a bladder tank. AMTROL's pioneering diaphragm design provides longest life and most complete water discharge. Benefits: Made in USA Unsurpassed customer service Expert technical support ISO Certified All models NSF Listed Industry's most comprehensive five-year warranty AMTROL invented technology 4 decades CE Features:: Fittings: 1/4" Size: 4.4 Gallons Storage Capacity: 2.8 Gallons Diameter: 11" Dia. x 15" Height