PTC heater, self controlling heater, long life, easy to assemble. Configuration.TypeSpecialtyExcellenceshortcomingOthersTransflux heaterWater transflux hole ... uses.Heating water for shower, ducking bath, footbath, washing hand, vegetable and dish. PTC water heater for drink warmer and boiler, vapor ... twice or decrease of 1/2, for the same PTC heater.