Used in the following models: 501, 651, 751, EP 150, EP 200, EP 250, EP 300, 502, 652, 752, EB 150, EW 150, EB 200, EW 200, EB 250, EW 250, EB 300, EW 300, CH 401, 401, CH 501, 501, CH 651, 651, CH 751, 751, CH 402, 402, CH 502, 502, CH 652, 652, CH 752, 752, Lochinvar Parts, Pool Heater Parts, Copper Fin II 501-2071