INKBIRD 1.97" Stainless Probe NTC-5CM Sensor Thermocouple DC Cord for Thermostat ITC-1000,ITC-306T, ITC-308S, ITC-310T Temperature Controller It's ONLY compatible with INKBIRD's following controllers: ITC-308,ITC-306T,ITC-310T, ITC-1000. NTC Temperature Sensor 1.97in Stainless Stell Probe with 6.5ft DC cord Easy to use Can be submersed into your beer direclty during fermentation. The sensor is waterproof and is better for the freshwater tank than the saltwater tank.