About heat transfer:
Inside the brass part, thermistor glass bead is in direct contact with brass stud. Also, heat conductivity of steel epoxy compound is relatively high and increasing speed of heat transfer. Compare this to regular approach, when thermistor is attached with kapton tape, and you will see that in both cases, glass bead of the termistor is touching heated metal surface, but with hex stud thermistor, metal surface is all around glass bead separated by very thin layer of epoxy. It works quite well, thousands are sold.
Witbox and
Prusa i3 Hephestos3D printers are equipped with this part.
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