Spa Solid State T-Stat 24VAC 5/16"x2` Thermister Manf. Tecmark Corporation Manf. # ETS100002402LP Tridelta Solid State Thermostat Hi performance solid state replacement thermostat. Pilot duty, 120v unit requires a neutral wire. Dimensions are 3.0"W x 1.8"H x 1.2"D. 12VAC model