Multi-Flue Commercial/Industrial Water Heaters Featuring Bock’s Legendary 3-Year Limited Warranty Multiple heat exchangers inside each unit with hundreds of turbofins to boost heat transfer -- faster heating water with less fuel. 166 to 275 Gallon Capacities 400,000 to 1,500,000 BTU Wet Leg Design - Combustion chamber is surrounded by water on all sides for continuous operation and...