Thermostatic Mixing Valve Model 220-USW for single- or multiple-outlet point-of-use or small hot water heater applications provides water temperature control at the source and is offered with union connections. Designed for lavatories, sinks and special washing applications, the valve features a responsive copper-encapsulated wax thermostat, locked temperature adjustment and integral check valves on the inlets. Leonard’s Thermostatic Mixing Valve is listed to ASSE Standards 1016 (1/2 inch, 3/4 inch or 3/8 inch) and 1017 (1/2 inch and 3/4 inch).