American Water Heaters, Raritan and Whirlpool are manufacturers of 12-gallon water heaters. All of the 12-gallon models these companies produce are 120V electrical heaters with five- or six-year warranties.
Twelve-gallon water heaters are among the smallest available. They're easy to position in areas with limited space, such as inside cabinets or under sinks. They're also useful for bars, workrooms, garages or any workspace that needs minimal access to hot water. Although the various brands are largely similar, there are some differences in construction. For example, it's important to inspect where the water valves are located on the tank to ensure installation is possible in the desired location.