Thermowell assemblies are used to hold inside one tube the rtd temperature sensor that monitors the temperature within the vessel in conjunction with a temperature controller. There are also tubes for addition of media and vent tube. Port Thermowell assembly For low profile 3l vessel Material: 316l SST with ra 32 or better – inside & out One vent port; .250"od x .152" id x 1.0"above & below cap slug One addition port: .250"od x .152"id x 17 1/8" insertion length One Thermowell port: .375"od x .305"id x 17 1/8" insertion length All tubes seam weld in to cap slug - bottom side only Supply with 45mm pp blue open top screw cap & white silicone gasket