Bosch AE-125 PowerStar Electric Tankless Water Heater With a 4.0 GPM Maximum Flow Rate Designed to replace a 40-gallon tank and provide endless hot water throughout the home. Delivers up to 4.0 gallons per minute for water usage at 105-F-2 sinks simultaneously or 1 shower or bathtub. Flow sensor ensures a constant output temperature. Thermal cutout for safety. External temperature control knob. No temperature/pressure relief valve is necessary (check local codes).