The Speakman Eyesaver SEF-TW Thermostatic Mixing Valve Kit is a thermostatic mixing valve kit for the SEF-1800 & SEF-9000. The SEF-TW features an SE-370 single element, thermostatic mixing valve capable of supplying 7 GPM of tepid water. The SE-370 provides 5 GPM cold water bypass in case of hot water or thermostatic element failure.