1/4 inch - weldless thermowell Stainless Steel 304 for Temperature Sensor Homebrew Brewing Thermometer Immersion Well 30 50 100 200 300 400 500mm (Length 50mm)

The first one I bought was great and is still lasting to this day. Latter I bought two more but noticed the hex nut was smaller. I thought no big deal and went ahead and installed them on a couple pool boilers. They began leaking after two months and corrosion was forming. They claim 304 stainless steel but I think they are really nickel coated. Mfg. from China was not helpful and went into denial. All they had to do was send me two replacements matching the original one I received and I would have been happy and written a good review.