Amtrol® EXTROL® Diaphragm Hydronic Expansion Tank, Vertical, Series: AX Series, 55.7 gal, 24 in Dia, 34 in Height, 125 psig, 22.6 gal Acceptance Capacity, 240 deg F, Heavy Duty Butyl/EPDM Diaphragm, Steel Shell, Red Oxide Primer, Domestic