Pentair 470184 Thermostat Knob Replacement Pool and Spa Heater Thermostat knob replacement Fits Pentair MiniMax NT STD heater with 6800 controller, NT LN heater with 6800 and DDTC controller, NT TSI heater with 6800 controller Also fits Pentair MiniMax CH heater model 150 IID Compatible with Pentair MiniMax Plus, PowerMax, MiniMax heater models 150, 200, 250, 300, 350, 400 Also compatible with Pentair MiniMax heater models 75, 100 and PowerMax and MiniMax commercial heaters