Rheem RTE 13 Electric Tankless Water Heater, 4 GPM On-unit temperature control, LEDs indicate active element and standby mode Standard 1/2" water connection Rugged brass/copper heat exchanger Modulating power. Specifications:Great for single shower applications, 240 Volts - 13KW, 4.0 GPM maximum flow rate Please refer the User Manual for installation instruction.