Amtrol expansion tank series available include Extrol, Fill-Trol and Radiant Extrol for heating applications, Well-X-Trol for well water and Therm-X-Trol for domestic hot water. Amtrol expansion tanks are made in the USA from highest quality materials and are the leading choice among professional contractors and homeowners alike. Amtrols' products are backed by 60 years of manufacturing experience and carry an industry-leading warranty.