Achieve precision temperature control with the Carboy Thermowell. This assembly includes a high-quality stainless steel thermowell tube and a specialized #6.5 silicone stopper. It allows you to place your digital temperature controller's probe directly into the heart of your fermenting wort or wine, providing a much more accurate reading than taping a probe to the exterior. The silicone stopper ensures a 100% airtight seal for 5 and 6-gallon carboys, protecting your batch from contaminants while monitoring its thermal profile.