www.pmmag.com/articles/88169-tank-in-tank-technology
Tank-In-Tank Technology
February 1, 2003
Triangle Tube announces the new Phase III Smart Line featuring its exclusive "tank-in-tank" technology. It is insulated with 2 inches of water-blown polyurethane foam, with an R-value of 16. It has a newly designed thermostat cover plate and is available in sizes from 20 through 80 gallons.
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