The Flo-Direct hot water heater fromArmstrong International, Inc. (Three Rivers, MI) features water temperatures from 130 degrees to 185 degrees F, which are available within 15 to 20 sec of the demand. Other features include a two-pass flow of hot gas to ensure a 98% or greater fuel efficiency, stainless steel construction, and no heat exchanger wall to separate the hot gas and water to minimize scale buildup.